Expose GroundScope struct

Reviewed-on: #19

README.md

@@ -75,15 +75,15 @@ build
         - [x] String operations
     - [x] Maths
     - [x] Comparisions
-    - [ ] Type conversions
+    - [x] Type conversions
     - [x] Functions
         - [x] Define functions
         - [x] Call functions
         - [x] Return values (type checked)
         - [x] Arguments for functions
         - [x] Jumping within functions
-    - [ ] Custom data structures
-    - [ ] Working with external libraries
+    - [x] Custom data structures
+    - [x] Working with external libraries
 
 ## Debugger
 
@@ -98,3 +98,26 @@ Commands:
 * eval (code): Runs Ground code in the current scope
 * help: Shows a help message
 
+## Compiler
+
+CGround now includes an experimental Ground -> x86_64 Linux ASM compiler. You can try it by adding the `-c` flag when running Ground. This will print the generated ASM to the console.
+
+At present only the `int` data type is supported.
+
+Supported instructions so far:
+
+* set
+* add
+* subtract
+* multiply
+* equal
+* inequal
+* greater
+* lesser
+* not
+* jump
+* if
+* @ (label creation)
+* print
+* println
+* end

docs/syntax.md

@@ -362,3 +362,23 @@ Looks in the path $GROUND_LIBS/`$libraryName`.grnd for the library. ($GROUND_LIB
 Attempts to import a shared library written in a compiled language like C or C++ for usage within the current program.
 
 Looks in the path $GROUND_LIBS/`$libraryName`.so for the library. ($GROUND_LIBS is a system environment variable.)
+
+### Data Structures
+
+#### struct -structName
+
+Creates a new struct which can be initialised. Until the endstruct keyword, the only valid instructions are init, set, fun, endfun, struct, and endstruct.
+
+Any value created inside the struct will be added to the struct.
+
+#### endstruct
+
+Ends the creation of a struct.
+
+#### getfield $object &fieldName &outputVar
+
+Gets a field from an initialised object. fieldName must be a valid name of a field in the object. Errors if the field does not exist. 
+
+#### setfield &object &fieldName $value
+
+Sets a field to a new value in the object. The value must be of the same type as the field's old value.

include/groundext.h

@@ -14,17 +14,6 @@ extern "C" {
 struct GroundScope;
 typedef struct GroundScope GroundScope;
 
-/*
- * Stores data associated with an error thrown during Ground execution.
- */
-typedef struct GroundError {
-    char* what;
-    char* type;
-    struct GroundInstruction* where;
-    size_t line;
-    bool hasLine;
-} GroundError;
-
 // Creates a GroundValue containing (in), with type ERROR.
 GroundValue createErrorGroundValue(GroundError in);
 

include/groundvm.h

@@ -1,5 +1,6 @@
 #ifndef LIBGROUND_H
 #define LIBGROUND_H
+#define MAX_ID_LEN 64
 
 /*
  * groundvm.h 
@@ -11,13 +12,15 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <uthash.h>
+
 
 typedef enum GroundInstType {
-    IF, JUMP, END, INPUT, PRINT, PRINTLN, SET, GETTYPE, EXISTS, SETLIST, SETLISTAT, GETLISTAT, GETLISTSIZE, LISTAPPEND, GETSTRSIZE, GETSTRCHARAT, ADD, SUBTRACT, MULTIPLY, DIVIDE, EQUAL, INEQUAL, NOT, GREATER, LESSER, STOI, STOD, TOSTRING, FUN, RETURN, ENDFUN, PUSHARG, CALL, STRUCT, ENDSTRUCT, INIT, USE, EXTERN, CREATELABEL, PAUSE, DROP
+    IF, JUMP, END, INPUT, PRINT, PRINTLN, SET, GETTYPE, EXISTS, SETLIST, SETLISTAT, GETLISTAT, GETLISTSIZE, LISTAPPEND, GETSTRSIZE, GETSTRCHARAT, ADD, SUBTRACT, MULTIPLY, DIVIDE, EQUAL, INEQUAL, NOT, GREATER, LESSER, STOI, STOD, ITOC, CTOI, TOSTRING, FUN, RETURN, ENDFUN, PUSHARG, CALL, STRUCT, ENDSTRUCT, INIT, GETFIELD, SETFIELD, USE, EXTERN, CREATELABEL, PAUSE, DROP, ERRORCMD
 } GroundInstType;
 
 typedef enum GroundValueType {
-    INT, DOUBLE, STRING, CHAR, BOOL, LIST, FUNCTION, CUSTOM, NONE
+    INT, DOUBLE, STRING, CHAR, BOOL, LIST, FUNCTION, STRUCTVAL, CUSTOM, ERROR, NONE
 } GroundValueType;
 
 typedef enum GroundArgType {
@@ -30,6 +33,7 @@ typedef enum ListAccessStatus {
 
 struct GroundValue;
 struct GroundFunction;
+struct GroundStruct;
 
 struct List;
 
@@ -41,20 +45,34 @@ typedef struct List {
     struct GroundValue* values;
 } List;
 
+/*
+ * Stores data associated with an error thrown during Ground execution.
+ */
+typedef struct GroundError {
+    char* what;
+    char* type;
+    struct GroundInstruction* where;
+    size_t line;
+    bool hasLine;
+} GroundError;
+
 /*
  * Stores literal values created in a Ground program.
  */
 typedef struct GroundValue {
     GroundValueType type;
-    union {
+    struct GroundStruct* customType;
+    struct {
         int64_t intVal;
         double doubleVal;
         char* stringVal;
         char charVal;
         bool boolVal;
         List listVal;
+        GroundError errorVal;
         struct GroundFunction* fnVal;
-        void* customVal;
+        struct GroundStruct* structVal;
+        struct GroundObject* customVal;
     } data;
 } GroundValue;
 
@@ -115,6 +133,57 @@ typedef struct GroundFunction {
     size_t startLine;
 } GroundFunction;
 
+/*
+ * Field for a GroundStruct
+ */
+typedef struct GroundStructField {
+    char id[64];
+    GroundValue value;
+    UT_hash_handle hh;
+} GroundStructField;
+
+/*
+ * Represents a Ground struct.
+ */
+typedef struct GroundStruct {
+    GroundStructField* fields;
+    size_t size;
+} GroundStruct;
+
+/*
+ * Field for a GroundObject
+ */
+typedef struct GroundObjectField {
+    char id[64];
+    GroundValue value;
+    UT_hash_handle hh;
+} GroundObjectField;
+
+/*
+ * Represents an initialised Ground struct.
+ */
+typedef struct GroundObject {
+    GroundObjectField* fields;
+} GroundObject;
+
+typedef struct GroundLabel {
+    char id[MAX_ID_LEN];
+    int lineNum;
+    UT_hash_handle hh;
+} GroundLabel;
+
+typedef struct GroundVariable {
+    char id[MAX_ID_LEN];
+    GroundValue value;
+    UT_hash_handle hh;
+} GroundVariable;
+
+typedef struct GroundScope {
+    GroundLabel** labels;
+    GroundVariable** variables;
+    bool isMainScope;
+} GroundScope;
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -123,16 +192,22 @@ GroundProgram groundCreateProgram();
 void groundAddInstructionToProgram(GroundProgram* program, GroundInstruction instruction);
 GroundValue groundRunProgram(GroundProgram* program);
 void groundPrintProgram(GroundProgram* program); 
+char* groundCompileProgram(GroundProgram* program);
 
 GroundInstruction groundCreateInstruction(GroundInstType type);
 void groundAddValueToInstruction(GroundInstruction* inst, GroundValue value);
 void groundAddReferenceToInstruction(GroundInstruction* inst, GroundArg value);
 GroundArg groundCreateReference(GroundArgType type, char* ref);
 
+void groundAddValueToScope(GroundScope* gs, const char* name, GroundValue value);
+
 GroundValue groundCreateValue(GroundValueType type, ...);
 
 GroundProgram groundParseFile(const char* code);
 
+GroundStruct groundCreateStruct();
+void groundAddFieldToStruct(GroundStruct* gstruct, char* name, GroundValue field);
+
 #ifdef __cplusplus
 }
 #endif

libs/math/math.c

@@ -1,5 +1,12 @@
 #include <groundext.h>
 #include <math.h>
+#include <time.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <limits.h>
+#include <float.h>
+
 
 GroundValue ground_sin(GroundScope* scope, List args) {
     return groundCreateValue(
@@ -21,19 +28,15 @@ GroundValue ground_tan(GroundScope* scope, List args) {
 }
 
 GroundValue rad_to_deg(GroundScope* scope, List args) {
-    double radians = args.values[0].data.doubleVal;
-
     return groundCreateValue(
         DOUBLE,
-        radians * (180.0 / M_PI)
+        args.values[0].data.doubleVal * (180.0 / M_PI)
     );
 }
 GroundValue deg_to_rad(GroundScope* scope, List args) {
-    double deg = args.values[0].data.doubleVal;
-
     return groundCreateValue(
         DOUBLE,
-        deg * (M_PI / 180.0)
+        args.values[0].data.doubleVal * (M_PI / 180.0)
     );
 }
 
@@ -62,16 +65,149 @@ GroundValue ground_sqrt(GroundScope* scope, List args) {
     );
 }
 
+GroundValue ground_abs(GroundScope* scope, List args) {
+    return groundCreateValue(
+        DOUBLE,
+        abs(args.values[0].data.doubleVal)
+    );
+}
+GroundValue ground_min(GroundScope* scope, List args) {
+    double a = args.values[0].data.doubleVal;
+    double b = args.values[1].data.doubleVal;
+
+    return groundCreateValue(
+        DOUBLE,
+        (a < b) ? a : b
+    );
+}
+GroundValue ground_max(GroundScope* scope, List args) {
+    double a = args.values[0].data.doubleVal;
+    double b = args.values[1].data.doubleVal;
+
+    return groundCreateValue(
+        DOUBLE,
+        (a > b) ? a : b
+    );
+}
+GroundValue ground_clamp(GroundScope* scope, List args) {
+    double number = args.values[0].data.doubleVal;
+    double min = args.values[1].data.doubleVal;
+    double max = args.values[2].data.doubleVal;
+
+    if (number < min) number = min;
+    if (number > max) number = max;
+
+    return groundCreateValue(
+        DOUBLE,
+        number
+    );
+}
+
+GroundValue ground_round(GroundScope* scope, List args) {
+    double x = args.values[0].data.doubleVal;
+
+    if (x >= 0.0)
+        return groundCreateValue(
+            INT,
+            (long long)(x + 0.5)
+        );
+    else
+        return groundCreateValue(
+            INT,
+            (long long)(x - 0.5)
+        );
+}
+GroundValue ground_floor(GroundScope* scope, List args) {
+    double x = args.values[0].data.doubleVal;
+
+    if (x >= (double)LLONG_MAX) return groundCreateValue(INT, LLONG_MAX);
+    if (x <= (double)LLONG_MIN) return groundCreateValue(INT, LLONG_MIN);
+
+    long long i = (long long)x; // truncates toward zero
+
+    if (x < 0 && x != (double)i) {
+        return groundCreateValue(
+            INT,
+            i-1
+        );
+    }
+
+    return groundCreateValue(
+        INT,
+        i
+    );
+}
+GroundValue ground_ceil(GroundScope* scope, List args) {
+    double x = args.values[0].data.doubleVal;
+
+    if (x >= (double)LLONG_MAX) return groundCreateValue(INT, LLONG_MAX);
+    if (x <= (double)LLONG_MIN) return groundCreateValue(INT, LLONG_MIN);
+
+    
+    long long i = (long long)x; // truncates toward zero
+
+    if (x > 0 && x != (double)i) {
+        return groundCreateValue(
+            INT,
+            i+1
+        );
+    }
+    
+    return groundCreateValue(
+        INT,
+        i
+    );
+}
+
+GroundValue ground_random(GroundScope* scope, List args) {
+    int64_t min = args.values[0].data.intVal;
+    int64_t max = args.values[1].data.intVal;
+
+    return groundCreateValue(
+        INT,
+        min + rand() % (max - min)
+    );
+}
+GroundValue ground_random_double(GroundScope* scope, List args) {
+    double min = args.values[0].data.doubleVal;
+    double max = args.values[1].data.doubleVal;
+
+    return groundCreateValue(
+        DOUBLE,
+        min + (double)rand() / RAND_MAX * (max - min)
+    );
+}
+GroundValue ground_random_set_seed(GroundScope* scope, List args) {
+    srand(args.values[0].data.intVal);
+    return groundCreateValue(
+        INT,
+        0
+    );
+}
+
 void ground_init(GroundScope* scope) {
+    srand((unsigned)time(NULL) ^ (unsigned)clock());
+
     groundAddNativeFunction(scope, "math_Sin", ground_sin, DOUBLE, 1, DOUBLE, "radians");
     groundAddNativeFunction(scope, "math_Cos", ground_cos, DOUBLE, 1, DOUBLE, "radians");
     groundAddNativeFunction(scope, "math_Tan", ground_tan, DOUBLE, 1, DOUBLE, "radians");
-
     groundAddNativeFunction(scope, "math_DegreesToRadians", deg_to_rad, DOUBLE, 1, DOUBLE, "degrees");
     groundAddNativeFunction(scope, "math_RadiansToDegrees", rad_to_deg, DOUBLE, 1, DOUBLE, "radians");
 
     groundAddNativeFunction(scope, "math_Modulos", ground_modulos, DOUBLE, 2, DOUBLE, "number1", DOUBLE, "number2");
     groundAddNativeFunction(scope, "math_Pow", ground_pow, DOUBLE, 2, DOUBLE, "number1", DOUBLE, "number2");
-
     groundAddNativeFunction(scope, "math_Sqrt", ground_sqrt, DOUBLE, 1, DOUBLE, "number");
+
+    groundAddNativeFunction(scope, "math_Abs", ground_abs, DOUBLE, 1, DOUBLE, "number");
+    groundAddNativeFunction(scope, "math_Min", ground_min, DOUBLE, 2, DOUBLE, "number1", DOUBLE, "number2");
+    groundAddNativeFunction(scope, "math_Max", ground_max, DOUBLE, 2, DOUBLE, "number1", DOUBLE, "number2");
+    groundAddNativeFunction(scope, "math_Clamp", ground_clamp, DOUBLE, 2, DOUBLE, "number", DOUBLE, "min", DOUBLE, "max");
+
+    groundAddNativeFunction(scope, "math_Round", ground_round, INT, 1, DOUBLE, "number");
+    groundAddNativeFunction(scope, "math_Floor", ground_floor, INT, 1, DOUBLE, "number");
+    groundAddNativeFunction(scope, "math_Ceil", ground_ceil, INT, 1, DOUBLE, "number");
+
+    groundAddNativeFunction(scope, "math_Random", ground_random, INT, 2, INT, "min", INT, "max");
+    groundAddNativeFunction(scope, "math_RandomDouble", ground_random_double, DOUBLE, 2, DOUBLE, "min", DOUBLE, "max");
+    groundAddNativeFunction(scope, "math_RandomSetSeed", ground_random_set_seed, INT, 1, INT, "seed");
 }

src/compiler.c

@@ -0,0 +1,541 @@
+#include "compiler.h"
+#include "interpreter.h"
+#include "types.h"
+#include "include/estr.h"
+#include <stdint.h>
+#include <inttypes.h>
+
+VariableTable createVariableTable() {
+    VariableTable vt;
+    vt.capacity = 16;
+    vt.count = 0;
+    vt.vars = malloc(sizeof(VariableInfo) * vt.capacity);
+    return vt;
+} 
+
+void addVtVariable(VariableTable* vt, const char* name) {
+    // check if it already exists
+    for (size_t i = 0; i < vt->count; i++) {
+        if (strcmp(vt->vars[i].name, name) == 0) {
+            return;
+        }
+    }
+
+    // increase capacity
+    if (vt->count >= vt->capacity) {
+        vt->capacity *= 2;
+        vt->vars = realloc(vt->vars, sizeof(VariableInfo) * vt->capacity);
+    }
+
+    // add the variable
+    strcpy(vt->vars[vt->count].name, name);
+    vt->vars[vt->count].offset = vt->count * 8;
+    vt->count++;
+}
+
+int getVariablePos(VariableTable* vt, const char* name) {
+    for (size_t i = 0; i < vt->count; i++) {
+        if (strcmp(vt->vars[i].name, name) == 0) {
+            return vt->vars[i].offset;
+        }
+    }
+    return -1;
+}
+
+char* processValueString(GroundArg arg) {
+    if (arg.type == VALREF) {
+        char* buf = malloc(sizeof(char) * 260);
+        snprintf(buf, sizeof(char) * 260, "[%s]", arg.value.refName);
+        return buf;
+    }
+    if (arg.type == VALUE) {
+        if (arg.value.value.type != INT) {
+            printf("Only int is supported right now\n");
+            exit(1);
+        }
+        char* buf = malloc(sizeof(char) * 64);
+        snprintf(buf, sizeof(char) * 260, "%" PRId64, arg.value.value.data.intVal);
+        return buf;
+    }
+    return NULL;
+}
+
+char* compileGroundProgram(GroundProgram* program) {
+    Estr start = CREATE_ESTR("global _start\nsection .text\n_start:\n");
+    Estr data = CREATE_ESTR("section .bss\n");
+    Estr helpers = CREATE_ESTR("");
+
+    APPEND_ESTR(helpers, "\n; Helper: Print integer in rax\n");
+    APPEND_ESTR(helpers, "print_int:\n");
+    APPEND_ESTR(helpers, "  push rbp\n");
+    APPEND_ESTR(helpers, "  mov rbp, rsp\n");
+    APPEND_ESTR(helpers, "  sub rsp, 32          ; Allocate buffer on stack\n");
+    APPEND_ESTR(helpers, "  mov rdi, rsp         ; RDI = buffer pointer\n");
+    APPEND_ESTR(helpers, "  add rdi, 31          ; Point to end of buffer\n");
+    APPEND_ESTR(helpers, "  mov byte [rdi], 0    ; Null terminator\n");
+    APPEND_ESTR(helpers, "  dec rdi\n");
+    APPEND_ESTR(helpers, "  mov rbx, 10          ; Divisor\n");
+    APPEND_ESTR(helpers, "  test rax, rax\n");
+    APPEND_ESTR(helpers, "  jns .positive\n");
+    APPEND_ESTR(helpers, "  neg rax              ; Make positive\n");
+    APPEND_ESTR(helpers, "  push rax\n");
+    APPEND_ESTR(helpers, "  mov byte [rdi], '-'\n");
+    APPEND_ESTR(helpers, "  dec rdi\n");
+    APPEND_ESTR(helpers, "  pop rax\n");
+    APPEND_ESTR(helpers, ".positive:\n");
+    APPEND_ESTR(helpers, "  xor rcx, rcx         ; Digit counter\n");
+    APPEND_ESTR(helpers, ".convert_loop:\n");
+    APPEND_ESTR(helpers, "  xor rdx, rdx\n");
+    APPEND_ESTR(helpers, "  div rbx              ; rax = rax/10, rdx = remainder\n");
+    APPEND_ESTR(helpers, "  add dl, '0'          ; Convert to ASCII\n");
+    APPEND_ESTR(helpers, "  mov [rdi], dl\n");
+    APPEND_ESTR(helpers, "  dec rdi\n");
+    APPEND_ESTR(helpers, "  inc rcx\n");
+    APPEND_ESTR(helpers, "  test rax, rax\n");
+    APPEND_ESTR(helpers, "  jnz .convert_loop\n");
+    APPEND_ESTR(helpers, "  inc rdi              ; Point back to first digit\n");
+    APPEND_ESTR(helpers, "  ; Now print the string\n");
+    APPEND_ESTR(helpers, "  mov rax, 1           ; sys_write\n");
+    APPEND_ESTR(helpers, "  mov rsi, rdi         ; Buffer\n");
+    APPEND_ESTR(helpers, "  mov rdx, rcx         ; Length\n");
+    APPEND_ESTR(helpers, "  mov rdi, 1           ; stdout\n");
+    APPEND_ESTR(helpers, "  syscall\n");
+    APPEND_ESTR(helpers, "  mov rsp, rbp\n");
+    APPEND_ESTR(helpers, "  pop rbp\n");
+    APPEND_ESTR(helpers, "  ret\n");
+
+    APPEND_ESTR(helpers, "\n; Helper: Print string at address in rax, length in rbx\n");
+    APPEND_ESTR(helpers, "print_string:\n");
+    APPEND_ESTR(helpers, "  push rax\n");
+    APPEND_ESTR(helpers, "  push rbx\n");
+    APPEND_ESTR(helpers, "  mov rdi, 1           ; stdout\n");
+    APPEND_ESTR(helpers, "  mov rsi, rax         ; String address\n");
+    APPEND_ESTR(helpers, "  mov rdx, rbx         ; Length\n");
+    APPEND_ESTR(helpers, "  mov rax, 1           ; sys_write\n");
+    APPEND_ESTR(helpers, "  syscall\n");
+    APPEND_ESTR(helpers, "  pop rbx\n");
+    APPEND_ESTR(helpers, "  pop rax\n");
+    APPEND_ESTR(helpers, "  ret\n");
+
+    VariableTable varTable = createVariableTable();
+
+    // Allocate a spot for all direct references
+    for (size_t i = 0; i < program->size; i++) {
+        GroundInstruction gi = program->instructions[i];
+        for (size_t j = 0; j < gi.args.length; j++) {
+            if (gi.args.args[j].type == DIRREF) {
+                addVtVariable(&varTable, gi.args.args[j].value.refName);
+            }
+        }
+    }
+
+    // Create data section
+    for (size_t i = 0; i < varTable.count; i++) {
+        if (strcmp(varTable.vars[i].name, "") == 0) {
+            continue;
+        }
+        APPEND_ESTR(data, "  ");
+        APPEND_ESTR(data, varTable.vars[i].name);
+        APPEND_ESTR(data, " resq 1\n");
+    }
+
+    // Generate assembly
+    for (size_t i = 0; i < program->size; i++) {
+        GroundInstruction gi = program->instructions[i];
+        switch (gi.type) {
+            case CREATELABEL: {
+                APPEND_ESTR(start, gi.args.args[0].value.refName);
+                APPEND_ESTR(start, ":\n");
+                break;
+            }
+            case SET: {
+                if (gi.args.length < 2) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.length > 2) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.args[0].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value for arg 2", &gi, i);
+                }
+
+                char* varName= gi.args.args[0].value.refName;
+
+                APPEND_ESTR(start, "  ; set\n")
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+
+                break;
+            }
+            case JUMP: {
+                if (gi.args.length < 1) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 1 arg", &gi, i);
+                }
+                if (gi.args.length > 1) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 1 arg", &gi, i);
+                }
+                if (gi.args.args[0].type != LINEREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a LineRef", &gi, i);
+                }
+
+                char* labelName = gi.args.args[0].value.refName;
+
+                APPEND_ESTR(start, "  ; jump\n");
+                APPEND_ESTR(start, "  jmp ");
+                APPEND_ESTR(start, labelName);
+                APPEND_ESTR(start, "\n");
+
+                break;
+            }
+            case IF: {
+                if (gi.args.length < 2) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.length > 2) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int (for now) for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != LINEREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a LineRef", &gi, i);
+                }
+
+                char* labelName = gi.args.args[1].value.refName;
+
+                APPEND_ESTR(start, "  ; if\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  test rax, rax\n");
+                APPEND_ESTR(start, "  jnz ");
+                APPEND_ESTR(start, labelName);
+                APPEND_ESTR(start, "\n");
+
+                break;
+            }
+            case NOT: {
+                if (gi.args.length < 2) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.length > 2) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int (for now) for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef", &gi, i);
+                }
+
+                char* varName = gi.args.args[1].value.refName;
+
+                APPEND_ESTR(start, "  ; not\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  xor rax, 1\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+
+                break;
+            }
+            case ADD: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for add instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for add instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; add\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  add rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case SUBTRACT: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for subtract instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for subtract instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; subtract\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  sub rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case MULTIPLY: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for multiply instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for multiply instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; multiply\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  imul rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case EQUAL: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for equal instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for equal instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; equal\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  cmp rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  sete al\n");
+                APPEND_ESTR(start, "  movzx rax, al\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case INEQUAL: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for inequal instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for inequal instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; inequal\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  cmp rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  setne al\n");
+                APPEND_ESTR(start, "  movzx rax, al\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case GREATER: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for greater instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for greater instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; greater\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  cmp rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  setg al\n");
+                APPEND_ESTR(start, "  movzx rax, al\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case LESSER: {
+                if (gi.args.length < 3) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 2 args for lesser instruction", &gi, i);
+                }
+                if (gi.args.length > 3) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 2 args for lesser instruction", &gi, i);
+                }
+                if (gi.args.args[0].type != VALUE && gi.args.args[0].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", &gi, i);
+                }
+                if (gi.args.args[1].type != VALUE && gi.args.args[1].type != VALREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 2", &gi, i);
+                }
+                if (gi.args.args[2].type != DIRREF) {
+                    runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", &gi, i);
+                }
+
+                char* varName= gi.args.args[2].value.refName;
+                APPEND_ESTR(start, "  ; lesser\n");
+                APPEND_ESTR(start, "  mov rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  cmp rax, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[1]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  setl al\n");
+                APPEND_ESTR(start, "  movzx rax, al\n");
+                APPEND_ESTR(start, "  mov [");
+                APPEND_ESTR(start, varName);
+                APPEND_ESTR(start, "], rax\n");
+                break;
+            }
+            case PRINT:
+            case PRINTLN: {
+                if (gi.args.length < 1) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 1 or more args", &gi, i);
+                }
+                
+                for (size_t j = 0; j < gi.args.length; j++) {
+                    if (gi.args.args[j].type != VALUE && gi.args.args[j].type != VALREF) {
+                        runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value", &gi, i);
+                    }
+                    if (j > 0) {
+                        // Print space between arguments
+                        APPEND_ESTR(start, "  ; print space\n");
+                        APPEND_ESTR(start, "  mov rax, 1\n");
+                        APPEND_ESTR(start, "  mov rdi, 1\n");
+                        APPEND_ESTR(start, "  lea rsi, [rel space_char]\n");
+                        APPEND_ESTR(start, "  mov rdx, 1\n");
+                        APPEND_ESTR(start, "  syscall\n");
+                    }
+                    APPEND_ESTR(start, "  ; print int\n");
+                    APPEND_ESTR(start, "  mov rax, ");
+                    APPEND_ESTR(start, processValueString(gi.args.args[j]));
+                    APPEND_ESTR(start, "\n");
+                    APPEND_ESTR(start, "  call print_int\n");
+                }
+                
+                if (gi.type == PRINTLN) {
+                    APPEND_ESTR(start, "  ; print newline\n");
+                    APPEND_ESTR(start, "  mov rax, 1\n");
+                    APPEND_ESTR(start, "  mov rdi, 1\n");
+                    APPEND_ESTR(start, "  lea rsi, [rel newline_char]\n");
+                    APPEND_ESTR(start, "  mov rdx, 1\n");
+                    APPEND_ESTR(start, "  syscall\n");
+                }
+                break;
+            }
+            case END: {
+                if (gi.args.length < 1) {
+                    runtimeError(TOO_FEW_ARGS, "Expecting 1 arg for end instruction", &gi, i);
+                }
+                if (gi.args.length > 1) {
+                    runtimeError(TOO_MANY_ARGS, "Expecting 1 arg for end instruction", &gi, i);
+                }
+                APPEND_ESTR(start, "  ; end\n");
+                APPEND_ESTR(start, "  mov rax, 60\n");
+                APPEND_ESTR(start, "  mov rdi, ");
+                APPEND_ESTR(start, processValueString(gi.args.args[0]));
+                APPEND_ESTR(start, "\n");
+                APPEND_ESTR(start, "  syscall\n");
+                break;
+            }
+            case DROP: {
+                // Drop does nothing in ground->asm as we use the stack
+                break;
+            }
+            default: {
+                printf("no\n");
+                exit(1);
+            }
+        }
+    }
+
+    Estr complete = CREATE_ESTR("");
+    APPEND_ESTR(complete, start.str);
+    APPEND_ESTR(complete, "  ; End of program\n  mov rax, 60\n  mov rdi, 0\n  syscall\n");
+    APPEND_ESTR(complete, helpers.str);
+    APPEND_ESTR(complete, "\nsection .rodata\n");
+    APPEND_ESTR(complete, "newline_char: db 10\n");
+    APPEND_ESTR(complete, "space_char: db 32\n");
+    APPEND_ESTR(complete, data.str)
+
+    return complete.str;
+}

src/compiler.h

@@ -0,0 +1,18 @@
+#include "types.h"
+#include "interpreter.h"
+
+char* compileGroundProgram(GroundProgram* program);
+[[noreturn]] void runtimeError(GroundRuntimeError error, char* what, GroundInstruction* where, int whereLine);
+
+typedef struct VariableInfo {
+    char name[256];
+    int offset;
+} VariableInfo;
+
+typedef struct VariableTable {
+    VariableInfo* vars;
+    size_t count;
+    size_t capacity;
+} VariableTable;
+
+

src/include/estr.h

@@ -0,0 +1,52 @@
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifndef ESTR_H
+#define ESTR_H
+
+/*
+
+    estr.h - Easy string manipulation
+    This library has macros to allow easier manipulation of strings. No longer shall
+    you have to malloc and realloc away to keep adding to your strings.
+
+    Usage:
+
+    Estr myString = CREATE_ESTR("my awesome string");
+    APPEND_ESTR(myString, " is so cool");
+    printf("%s\n", myString.str);
+
+*/
+
+#define CREATE_ESTR(instr) \
+    (Estr) { \
+        .str = instr,\
+        .size = strlen(instr),\
+        .shouldBeFreed = 0, \
+        .destroyed = 0 \
+    }
+
+#define APPEND_ESTR(estr, instr) { \
+    estr.size = estr.size + strlen(instr); \
+    char* tmp_ptr = malloc(estr.size + 1); \
+    if (tmp_ptr == NULL) printf("WARNING: Could not realloc estr " #estr "\n"); \
+    else { \
+        snprintf(tmp_ptr, estr.size + 1, "%s%s", estr.str, instr); \
+        if (estr.shouldBeFreed > 0) free(estr.str); \
+        estr.shouldBeFreed = 1; \
+        estr.str = tmp_ptr; \
+    } \
+}
+
+#define DESTROY_ESTR(estr) if (estr.shouldBeFreed > 0 && estr.destroyed < 1) free(estr.str); 
+
+typedef struct Estr {
+    char* str;
+    size_t size;
+    int8_t shouldBeFreed;
+    int8_t destroyed;
+} Estr; 
+
+#endif // ESTR_H

src/interface.c

@@ -1,6 +1,6 @@
-#include "lexer.h"
 #include "parser.h"
 #include "interpreter.h"
+#include "compiler.h"
 #include "types.h"
 
 #include <stdlib.h>
@@ -68,11 +68,30 @@ GroundValue groundCreateValue(GroundValueType type, ...) {
             return createListGroundValue(va_arg(args, List));
             break;
         }
-        default: {
+        case FUNCTION: {
+            return createFunctionGroundValue(va_arg(args, GroundFunction*));
+            break;
+        }
+        case STRUCTVAL: {
+            GroundValue gv;
+            gv.type = STRUCTVAL;
+            gv.data.structVal = malloc(sizeof(GroundStruct));
+            *gv.data.structVal = va_arg(args, GroundStruct);
+            return gv;
+        }
+        case NONE: {
             return createNoneGroundValue();
+            break;
+        }
+        case ERROR:
+        case CUSTOM: {
+            // FIXME
+            break;
         }
     }
 
+    return createNoneGroundValue();
+
     va_end(args);
 }
 
@@ -90,3 +109,22 @@ void groundPrintProgram(GroundProgram* program) {
 GroundProgram groundParseFile(const char* code) {
     return parseFile(code);
 }
+
+GroundStruct groundCreateStruct() {
+    GroundStruct gs;
+    gs.size = 0;
+    gs.fields = malloc(sizeof(GroundStructField));
+    return gs;
+}
+
+void groundAddValueToScope(GroundScope* gs, const char* name, GroundValue value) {
+    addVariable(gs->variables, name, value);
+}
+
+void groundAddFieldToStruct(GroundStruct* gstruct, char* name, GroundValue field) {
+    addFieldToStruct(gstruct, name, field);
+}
+
+char* groundCompileProgram(GroundProgram* program) {
+    return compileGroundProgram(program);
+}

src/interpreter.c

@@ -5,7 +5,9 @@
 #include <inttypes.h>
 #include <stdlib.h>
 #include <string.h>
+#ifndef _WIN32
 #include <dlfcn.h>
+#endif
 #include <stdarg.h>
 #include <unistd.h>
 
@@ -13,6 +15,23 @@ int currentInstruction = 0;
 
 bool isMainScopeGlobal = true;
 
+[[noreturn]] void customError(GroundArg type, GroundArg what, GroundInstruction* where, int whereLine, int exitCode) {
+    printf("Ground runtime error:\n  ErrorType: ");
+    printGroundArg(&type);
+    printf("\n  ErrorContext: ");
+    printGroundArg(&what);
+    printf("\n");
+    if (where != NULL) {
+        printf("  ErrorInstruction: ");
+        printGroundInstruction(where);
+        printf("\n");
+    }
+    if (whereLine > -1) {
+        printf("  ErrorLine: %d\n", whereLine + 1);
+    }
+    exit(exitCode);
+}
+
 [[noreturn]] void runtimeError(GroundRuntimeError error, char* what, GroundInstruction* where, int whereLine) {
     printf("Ground runtime error:\n  ErrorType: ");
     switch (error) {
@@ -335,7 +354,7 @@ GroundStruct parseStruct(GroundProgram* in, GroundScope* scope, size_t errorOffs
 
                 GroundValue gv;
 
-                switch (stringToValueType(in->instructions[i].args.args[0].value.refName)) {
+                switch (stringToValueType(in->instructions[i].args.args[1].value.refName)) {
                     case INT: {
                         gv = createIntGroundValue(0);
                         break;
@@ -382,6 +401,7 @@ GroundStruct parseStruct(GroundProgram* in, GroundScope* scope, size_t errorOffs
                         gv.type = CUSTOM;
                         gv.data.customVal = malloc(sizeof(GroundObject));
                         *gv.data.customVal = createObject(*gstruct);
+                        gv.customType = gstruct;
                         break;
                     }
                     case NONE: {
@@ -425,6 +445,7 @@ GroundStruct parseStruct(GroundProgram* in, GroundScope* scope, size_t errorOffs
                     addInstructionToProgram(&gp, in->instructions[i]);
                     i++;
                 }
+                i--;
 
                 GroundFunction* function = parseFunction(&gp, errorOffset);
                 function->startLine = i;
@@ -491,6 +512,7 @@ GroundValue interpretGroundProgram(GroundProgram* in, GroundScope* inScope) {
                 addInstructionToProgram(&gp, in->instructions[i]);
                 i++;
             }
+            i--;
 
             GroundFunction* function = parseFunction(&gp, errorOffset);
             function->startLine = i;
@@ -528,6 +550,7 @@ GroundValue interpretGroundProgram(GroundProgram* in, GroundScope* inScope) {
                 addInstructionToProgram(&gp, in->instructions[i]);
                 i++;
             }
+            i--;
 
             GroundValue gv = {
                 .type = STRUCTVAL,
@@ -813,7 +836,19 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
             }
             break;
         }
+        case ERRORCMD: {
+            if (in->args.length < 3) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 3 args", in, currentInstruction);
+            } else if (in->args.length > 3) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 3 args", in, currentInstruction);
+            }
+            if (in->args.args[2].value.value.type != INT ) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting an int for arg 2", in, currentInstruction);
+            }
             
+            customError(in->args.args[0], in->args.args[1], in, currentInstruction, in->args.args[2].value.value.data.intVal);
+            break;
+        }
         /*
          * VARIABLES AND LISTS
          * These instructions are for initializing variables and lists.
@@ -1074,7 +1109,7 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
             if (in->args.args[1].type != DIRREF) {
                 runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
             }
-            addVariable(scope->variables, in->args.args[2].value.refName, createIntGroundValue(atoll(in->args.args[0].value.value.data.stringVal)));
+            addVariable(scope->variables, in->args.args[1].value.refName, createIntGroundValue(atoll(in->args.args[0].value.value.data.stringVal)));
             break;
         }
         case STOD: {
@@ -1090,7 +1125,39 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
             if (in->args.args[1].type != DIRREF) {
                 runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
             }
-            addVariable(scope->variables, in->args.args[1].value.refName, createIntGroundValue(atof(in->args.args[0].value.value.data.stringVal)));
+            addVariable(scope->variables, in->args.args[1].value.refName, createDoubleGroundValue(atof(in->args.args[0].value.value.data.stringVal)));
+            break;
+        }
+        case ITOC: {
+            if (in->args.length < 2) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 2 args", in, currentInstruction);
+            }
+            if (in->args.length > 2) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 2 args", in, currentInstruction);
+            }
+            if (in->args.args[0].type != VALUE || in->args.args[0].value.value.type != INT) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting an Int for arg 1", in, currentInstruction);
+            }
+            if (in->args.args[1].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
+            }
+            addVariable(scope->variables, in->args.args[1].value.refName, createCharGroundValue((char)in->args.args[0].value.value.data.intVal));
+            break;
+        }
+        case CTOI: {
+            if (in->args.length < 2) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 2 args", in, currentInstruction);
+            }
+            if (in->args.length > 2) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 2 args", in, currentInstruction);
+            }
+            if (in->args.args[0].type != VALUE || in->args.args[0].value.value.type != CHAR) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a Char for arg 1", in, currentInstruction);
+            }
+            if (in->args.args[1].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
+            }
+            addVariable(scope->variables, in->args.args[1].value.refName, createIntGroundValue((int)in->args.args[0].value.value.data.charVal));
             break;
         }
         case TOSTRING: {
@@ -1107,57 +1174,53 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
                 runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
             }
             GroundValue* value = &in->args.args[0].value.value;
+            char buf[256];
             switch (value->type) {
                 case INT: {
-                    char* buf = malloc(sizeof(char) * 256);
-                    snprintf(buf, sizeof(char) * 256, "%" PRId64, value->data.intVal);
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue(buf));
+                    snprintf(buf, sizeof(buf) * 256, "%" PRId64, value->data.intVal);
                     break;
                 }
                 case DOUBLE: {
-                    char* buf = malloc(sizeof(char) * 256);
-                    snprintf(buf, sizeof(char) * 256, "%f", value->data.doubleVal);
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue(buf));
+                    snprintf(buf, sizeof(buf) * 256, "%f", value->data.doubleVal);
                     break;
                 }
                 case STRING: {
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue(value->data.stringVal));
+                    snprintf(buf, sizeof(buf), "%s", value->data.stringVal);
                     break;
                 }
                 case CHAR: {
-                    char* buf = malloc(sizeof(char) * 2);
                     buf[0] = value->data.charVal;
                     buf[1] = '\0';
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue(buf));
                     break;
                 }
                 case BOOL: {
                     if (value->data.boolVal) {
-                        addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("true"));
+                        snprintf(buf, sizeof(buf), "true");
                     } else {
-                        addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("false"));
+                        snprintf(buf, sizeof(buf), "false");
                     }
                     break;
                 }
                 case LIST: {
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("<list>"));
+                    snprintf(buf, sizeof(buf), "<list>");
                     break;
                 }
                 case FUNCTION: {
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("<function>"));
+                    snprintf(buf, sizeof(buf), "<function>");
                     break;
                 }
                 case CUSTOM: {
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("<custom>"));
+                    snprintf(buf, sizeof(buf), "<custom>");
                     break;
                 }
                 case NONE:
                 default: {
-                    addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue("<default>"));
+                    snprintf(buf, sizeof(buf), "<default>");
                     break;
 
                 }
             }
+            addVariable(scope->variables, in->args.args[1].value.refName, createStringGroundValue(buf));
 
             break;
         }
@@ -1753,7 +1816,8 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
                     if (in->args.args[i + 1].type != VALUE) {
                         runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value", in, currentInstruction);
                     }
-                    if (in->args.args[i + 1].value.value.type != function->args[i].type) {
+                    //if (in->args.args[i + 1].value.value.type != function->args[i].type) {
+                    if (!checkFnTypes(&in->args.args[i + 1].value.value, &function->args[i])) {
                         runtimeError(ARG_TYPE_MISMATCH, "Mismatched function argument types", in, currentInstruction);
                     }
                     appendToList(&argsList, in->args.args[i + 1].value.value);
@@ -1781,7 +1845,8 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
                     if (in->args.args[i + 1].type != VALUE) {
                         runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value", in, currentInstruction);
                     }
-                    if (in->args.args[i + 1].value.value.type != function->args[i].type) {
+                    //if (in->args.args[i + 1].value.value.type != function->args[i].type) {
+                    if (!checkFnTypes(&in->args.args[i + 1].value.value, &function->args[i])) {
                         runtimeError(ARG_TYPE_MISMATCH, "Mismatched function argument types", in, currentInstruction);
                     }
                     addVariable(newScope.variables, function->args[i].name, in->args.args[i + 1].value.value);
@@ -1862,6 +1927,10 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
         }
 
         case EXTERN: {
+	    #ifdef _WIN32
+	    runtimeError(FIXME, "No Windows support for extern, sucker", in, currentInstruction);
+	    #endif
+	    #ifndef _WIN32
             if (in->args.length < 1) {
                 runtimeError(TOO_FEW_ARGS, "Expecting 1 arg", in, currentInstruction);
             }
@@ -1911,6 +1980,7 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
             }
             
             initFn(scope);
+	    #endif
             break;
         }
 
@@ -1979,6 +2049,7 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
                     gv.type = CUSTOM;
                     gv.data.customVal = malloc(sizeof(GroundObject));
                     *gv.data.customVal = createObject(*gstruct);
+                    gv.customType = gstruct;
                     break;
                 }
                 case NONE: {
@@ -1995,6 +2066,77 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
             break;
         }
 
+        /*
+         * OBJECTS
+         * Allows manipulation of Ground objects.
+         */
+        // getfield $obj &field &result
+        case GETFIELD: {
+            if (in->args.length < 3) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 3 args", in, currentInstruction);
+            }
+            if (in->args.length > 3) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 3 args", in, currentInstruction);
+            }
+            if (in->args.args[0].type != VALUE) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting an Object for arg 1", in, currentInstruction);
+            }
+            if (in->args.args[0].value.value.type != CUSTOM) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting an Object for arg 1", in, currentInstruction);
+            }
+            if (in->args.args[1].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
+            }
+            if (in->args.args[2].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 3", in, currentInstruction);
+            }
+
+            GroundObjectField* field = findField(*in->args.args[0].value.value.data.customVal, in->args.args[1].value.refName);
+            if (field == NULL) {
+                runtimeError(UNKNOWN_VARIABLE, "Struct does not contain that field", in, currentInstruction);
+            }
+            addVariable(scope->variables, in->args.args[2].value.refName, field->value);
+            
+            break;
+        }
+        // setfield &obj &field $value
+        case SETFIELD: {
+            if (in->args.length < 3) {
+                runtimeError(TOO_FEW_ARGS, "Expecting 3 args", in, currentInstruction);
+            }
+            if (in->args.length > 3) {
+                runtimeError(TOO_MANY_ARGS, "Expecting 3 args", in, currentInstruction);
+            }
+            if (in->args.args[0].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef to an Object for arg 1", in, currentInstruction);
+            }
+            if (in->args.args[1].type != DIRREF) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef for arg 2", in, currentInstruction);
+            }
+            if (in->args.args[2].type != VALUE) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a Value for arg 3", in, currentInstruction);
+            }
+
+            GroundVariable* var = findVariable(*scope->variables, in->args.args[0].value.refName);
+            if (var == NULL) {
+                runtimeError(UNKNOWN_VARIABLE, "Could not find that object", in, currentInstruction);
+            }
+            if (var->value.type != CUSTOM) {
+                runtimeError(ARG_TYPE_MISMATCH, "Expecting a DirectRef to an Object for arg 1", in, currentInstruction);
+            }
+
+            GroundObjectField* field = findField(*var->value.data.customVal, in->args.args[1].value.refName);
+            if (field == NULL) {
+                runtimeError(UNKNOWN_VARIABLE, "Struct does not contain that field", in, currentInstruction);
+            }
+            if (field->value.type != in->args.args[2].value.value.type) {
+                runtimeError(ARG_TYPE_MISMATCH, "Field type and provided type do not match", in, currentInstruction);
+            }
+
+            field->value = copyGroundValue(&in->args.args[2].value.value);
+            break;
+        }
+
         case DROP: {
             if (in->args.length < 1) {
                 runtimeError(TOO_FEW_ARGS, "Expecting 1 arg", in, currentInstruction);

src/interpreter.h

@@ -42,6 +42,7 @@ GroundFunction* parseFunction(GroundProgram* in, size_t errorOffset);
 GroundValue interpretGroundProgram(GroundProgram* in, GroundScope* inScope);
 GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scope);
 
+void addVariable(GroundVariable **head, const char *id, GroundValue data);
 
 
 

src/main.c

@@ -1,5 +1,7 @@
 #include "parser.h"
 #include "interpreter.h"
+#include "compiler.h"
+#include "types.h"
 #include <stdio.h>
 
 char* getFileContents(const char* filename) {
@@ -40,11 +42,55 @@ char* getFileContents(const char* filename) {
 
 int main(int argc, char** argv) {
     if (argc < 2) {
-        printf("Usage: ground [file]\n");
+        printf("Usage: %s <file> [-c] [--compile] [-h] [--help]\n", argv[0]);
         exit(1);
     }
-    char* file = getFileContents(argv[1]);
+
+    bool compile = false;
+    char* fileName = NULL;
+    List groundArgs = createList();
+    for (int i = 1; i < argc; i++) {
+        if (strcmp("--compile", argv[i]) == 0 || strcmp("-c", argv[i]) == 0) {
+            compile = true;
+        }
+        else if (strcmp("--help", argv[i]) == 0 || strcmp("-h", argv[i]) == 0) {
+            printf("GroundVM help\n");
+            printf("Usage: %s <file> [-c] [--compile] [-h] [--help]\n", argv[0]);
+            printf("Options:\n");
+            printf("  -c or --compile: Outputs Linux x86_64 assembly instead of interpreting (WIP)\n");
+            printf("  -h or --help: Shows this help message\n");
+            exit(0);
+        } else {
+            if (fileName == NULL) {
+                fileName = argv[i];
+            } else {
+                appendToList(&groundArgs, createStringGroundValue(argv[i]));
+            }
+        }
+    }
+
+    if (fileName == NULL) {
+        printf("Usage: %s <file> [-c] [--compile] [-h] [--help]\n", argv[0]);
+        printf("Error: No file name provided\n");
+        exit(1);
+    }
+
+    char* file = getFileContents(fileName);
     GroundProgram program = parseFile(file);
     free(file);
-    interpretGroundProgram(&program, NULL);
+
+    if (compile) {
+        char* compiled = compileGroundProgram(&program);
+        printf("%s\n", compiled);
+    } else {
+        GroundVariable* variables = NULL;
+        GroundLabel* labels = NULL;
+
+        GroundScope scope;
+        scope.variables = &variables;
+        scope.labels = &labels;
+        scope.isMainScope = true;
+        addVariable(scope.variables, "CMDLINE_ARGS", createListGroundValue(groundArgs));
+        interpretGroundProgram(&program, &scope);
+    }
 }

src/parser.c

@@ -5,6 +5,25 @@
 #include <string.h>
 #include <ctype.h>
 
+#ifdef _WIN32
+size_t strnlen(const char *src, size_t n) {
+    size_t len = 0;
+    while (len < n && src[len])
+        len++;
+    return len;
+}
+
+char* strndup(const char *s, size_t n) {
+    size_t len = strnlen(s, n);
+    char *p = malloc(len + 1);
+    if (p) {
+        memcpy(p, s, len);
+        p[len] = '\0';
+    }
+    return p;
+}
+#endif
+
 GroundProgram createGroundProgram() {
     GroundProgram gp;
     gp.size = 0;
@@ -137,6 +156,7 @@ static GroundInstType getInstructionType(const char* inst) {
     if (strcmp(inst, "input") == 0 || strcmp(inst, "stdin") == 0) return INPUT;
     if (strcmp(inst, "print") == 0 || strcmp(inst, "stdout") == 0) return PRINT;
     if (strcmp(inst, "println") == 0 || strcmp(inst, "stdlnout") == 0) return PRINTLN;
+    if (strcmp(inst, "error") == 0) return ERRORCMD;
     if (strcmp(inst, "set") == 0) return SET;
     if (strcmp(inst, "gettype") == 0) return GETTYPE;
     if (strcmp(inst, "exists") == 0) return EXISTS;
@@ -158,6 +178,8 @@ static GroundInstType getInstructionType(const char* inst) {
     if (strcmp(inst, "lesser") == 0) return LESSER;
     if (strcmp(inst, "stoi") == 0) return STOI;
     if (strcmp(inst, "stod") == 0) return STOD;
+    if (strcmp(inst, "ctoi") == 0) return CTOI;
+    if (strcmp(inst, "itoc") == 0) return ITOC;
     if (strcmp(inst, "tostring") == 0) return TOSTRING;
     if (strcmp(inst, "fun") == 0) return FUN;
     if (strcmp(inst, "return") == 0) return RETURN;
@@ -167,6 +189,8 @@ static GroundInstType getInstructionType(const char* inst) {
     if (strcmp(inst, "struct") == 0) return STRUCT;
     if (strcmp(inst, "endstruct") == 0) return ENDSTRUCT;
     if (strcmp(inst, "init") == 0) return INIT;
+    if (strcmp(inst, "getfield") == 0) return GETFIELD;
+    if (strcmp(inst, "setfield") == 0) return SETFIELD;
     if (strcmp(inst, "use") == 0) return USE;
     if (strcmp(inst, "extern") == 0) return EXTERN;
     if (strcmp(inst, "drop") == 0) return DROP;

src/types.c

@@ -90,16 +90,55 @@ GroundValue copyGroundValue(const GroundValue* gv) {
         }
         case FUNCTION: newGv.data.fnVal = gv->data.fnVal; break;
         case STRUCTVAL: {
-            // do this later lmao
-            // FIXME
-            newGv.data.structVal = gv->data.structVal;
+            newGv.data.structVal = malloc(sizeof(GroundStruct));
+            if (newGv.data.structVal == NULL) {
+                printf("Couldn't allocate memory for GroundStruct copy\n");
+                exit(1);
+            }
+            
+            newGv.data.structVal->size = gv->data.structVal->size;
+            newGv.data.structVal->fields = malloc(gv->data.structVal->size * sizeof(GroundStructField));
+            if (newGv.data.structVal->fields == NULL && gv->data.structVal->size > 0) {
+                printf("Couldn't allocate memory for GroundStruct fields copy\n");
+                exit(1);
+            }
+            
+            for (size_t i = 0; i < gv->data.structVal->size; i++) {
+                strncpy(newGv.data.structVal->fields[i].id, 
+                        gv->data.structVal->fields[i].id, 
+                        sizeof(newGv.data.structVal->fields[i].id) - 1);
+                newGv.data.structVal->fields[i].id[sizeof(newGv.data.structVal->fields[i].id) - 1] = '\0';
+                
+                newGv.data.structVal->fields[i].value = copyGroundValue(&gv->data.structVal->fields[i].value);
+            }
             break;
         }
-        case CUSTOM:
-            // also do this later
-            // FIXME
-            newGv.data.customVal = gv->data.customVal;
+        case CUSTOM: {
+            newGv.customType = gv->customType;
+            newGv.data.customVal = malloc(sizeof(GroundObject));
+            if (newGv.data.customVal == NULL) {
+                printf("Couldn't allocate memory for GroundObject copy\n");
+                exit(1);
+            }
+            
+            newGv.data.customVal->fields = NULL;
+            
+            GroundObjectField *field, *tmp;
+            HASH_ITER(hh, gv->data.customVal->fields, field, tmp) {
+                GroundObjectField* newField = malloc(sizeof(GroundObjectField));
+                if (newField == NULL) {
+                    printf("Couldn't allocate memory for GroundObjectField copy\n");
+                    exit(1);
+                }
+                
+                strncpy(newField->id, field->id, sizeof(newField->id) - 1);
+                newField->id[sizeof(newField->id) - 1] = '\0';
+                newField->value = copyGroundValue(&field->value);
+                
+                HASH_ADD_STR(newGv.data.customVal->fields, id, newField);
+            }
             break;
+        }
         case NONE:
         default: {
 
@@ -149,8 +188,47 @@ void printGroundValue(GroundValue* gv) {
             printf("<function>");
             break;
         }
-        default: {
-            printf("FIXME");
+        case STRUCTVAL: {
+            printf("<struct fields: { ");
+            for (size_t i = 0; i < gv->data.structVal->size; i++) {
+                if (i != 0) {
+                    printf(", ");
+                }
+                printf("%s: ", gv->data.structVal->fields[i].id);
+                if (gv->data.structVal->fields[i].value.type == STRING) {
+                    printf("\"");
+                    printGroundValue(&gv->data.structVal->fields[i].value);
+                    printf("\"");
+                } else {
+                    printGroundValue(&gv->data.structVal->fields[i].value);
+                }
+            }
+            printf(" }>");
+            break;
+        }
+        case CUSTOM: {
+            printf("<object fields: { ");
+            for (size_t i = 0; i < gv->customType->size; i++) {
+                if (i != 0) {
+                    printf(", ");
+                }
+                printf("%s: ", gv->customType->fields[i].id);
+                GroundObjectField* field = findField(*gv->data.customVal, gv->customType->fields[i].id);
+                if (field == NULL) {
+                    printf("<missing>");
+                } else {
+                    printGroundValue(&field->value);
+                }
+            }
+            printf(" }>");
+            break;
+        }
+        case ERROR: {
+            printf("<error type: %s, what: %s>", gv->data.errorVal.type, gv->data.errorVal.what);
+            break;
+        }
+        case NONE: {
+            printf("<none>");
             break;
         }
     }
@@ -374,6 +452,12 @@ void printGroundInstruction(GroundInstruction* gi) {
         case STOD:
             printf("stod");
             break;
+        case CTOI:
+            printf("ctoi");
+            break;
+        case ITOC:
+            printf("itoc");
+            break;
         case TOSTRING:
             printf("tostring");
             break;
@@ -412,6 +496,9 @@ void printGroundInstruction(GroundInstruction* gi) {
             break;
         case CREATELABEL:
             break;
+        case ERRORCMD:
+            printf("error");
+            break;
         default:
             printf("FIXME");
             break;
@@ -582,3 +669,43 @@ GroundError createGroundError(char* what, char* type, GroundInstruction* where,
 
     return ge;
 }
+
+bool checkFnTypes(GroundValue* left, GroundFunctionArgs* right) {
+    if (left->type != right->type) {
+        return false;
+    }
+    if (left->type == CUSTOM) {
+        if (left->customType->size != right->customType->size) {
+            return false;
+        }
+        for (size_t i = 0; i < left->customType->size; i++) {
+            if (strcmp(left->customType->fields[i].id, right->customType->fields[i].id) != 0) {
+                return false;
+            }
+            if (!checkTypes(&left->customType->fields[i].value, &right->customType->fields[i].value)) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+bool checkTypes(GroundValue* left, GroundValue* right) {
+    if (left->type != right->type) {
+        return false;
+    }
+    if (left->type == CUSTOM) {
+        if (left->customType->size != right->customType->size) {
+            return false;
+        }
+        for (size_t i = 0; i < left->customType->size; i++) {
+            if (strcmp(left->customType->fields[i].id, right->customType->fields[i].id) != 0) {
+                return false;
+            }
+            if (!checkTypes(&left->customType->fields[i].value, &right->customType->fields[i].value)) {
+                return false;
+            } 
+        }
+    }
+    return true;
+}

src/types.h

@@ -9,7 +9,7 @@
 #include "include/uthash.h"
 
 typedef enum GroundInstType {
-    IF, JUMP, END, INPUT, PRINT, PRINTLN, SET, GETTYPE, EXISTS, SETLIST, SETLISTAT, GETLISTAT, GETLISTSIZE, LISTAPPEND, GETSTRSIZE, GETSTRCHARAT, ADD, SUBTRACT, MULTIPLY, DIVIDE, EQUAL, INEQUAL, NOT, GREATER, LESSER, STOI, STOD, TOSTRING, FUN, RETURN, ENDFUN, PUSHARG, CALL, STRUCT, ENDSTRUCT, INIT, USE, EXTERN, CREATELABEL, PAUSE, DROP
+    IF, JUMP, END, INPUT, PRINT, PRINTLN, SET, GETTYPE, EXISTS, SETLIST, SETLISTAT, GETLISTAT, GETLISTSIZE, LISTAPPEND, GETSTRSIZE, GETSTRCHARAT, ADD, SUBTRACT, MULTIPLY, DIVIDE, EQUAL, INEQUAL, NOT, GREATER, LESSER, STOI, STOD, ITOC, CTOI, TOSTRING, FUN, RETURN, ENDFUN, PUSHARG, CALL, STRUCT, ENDSTRUCT, INIT, GETFIELD, SETFIELD, USE, EXTERN, CREATELABEL, PAUSE, DROP, ERRORCMD
 } GroundInstType;
 
 typedef enum GroundValueType {
@@ -62,7 +62,8 @@ typedef struct GroundError {
  */
 typedef struct GroundValue {
     GroundValueType type;
-    union {
+    struct GroundStruct* customType;
+    struct {
         int64_t intVal;
         double doubleVal;
         char* stringVal;
@@ -125,6 +126,7 @@ typedef struct GroundProgram {
  */
 typedef struct GroundFunctionArgs {
     GroundValueType type;
+    struct GroundStruct* customType;
     char* name;
 } GroundFunctionArgs;
 
@@ -276,6 +278,11 @@ void freeGroundObject(GroundObject* object);
 // Creates a GroundError.
 GroundError createGroundError(char* what, char* type, GroundInstruction* where, size_t* line);
 
+// Compares types of a value and function args. 
+bool checkFnTypes(GroundValue* left, GroundFunctionArgs* arg);
+
+// Compares types of two values.
+bool checkTypes(GroundValue* left, GroundValue* right);
 
 
 #endif

tests/convs.grnd

@@ -1,3 +1,11 @@
-tostring 32 &int
+tostring 32 &str
+stoi "12" &int
+stod "3.14" &dou
+itoc 353 &chr
+ctoi 'a' &it2
 
+println $str
 println $int
+println $dou
+println $chr
+println $it2

tests/error.grnd

@@ -0,0 +1,2 @@
+setlist &dat 1 2 3 "Hi!"
+error "Hello" $dat 1

tests/struct.grnd

@@ -0,0 +1,17 @@
+struct -point
+
+    init &x -int
+    init &y -int
+
+endstruct
+
+init &mypoint -point
+
+setfield &mypoint &x 53
+setfield &mypoint &y 32
+
+getfield $mypoint &x &value
+println $value
+
+getfield $mypoint &y &value
+println $value