From 34afdd9642055c3e63c78bf5a18801d06659c837 Mon Sep 17 00:00:00 2001
From: Maxwell Jeffress <maxwelljeffress@proton.me>
Date: Sat, 1 Aug 2026 20:43:16 +1000
Subject: [PATCH] Function parsing!

---
 src/main.cpp          | 17 +++++++-
 src/parser/parser.cpp | 97 ++++++++++++++++++++++++++++++++++++++++++-
 src/parser/parser.hpp |  1 +
 3 files changed, 112 insertions(+), 3 deletions(-)

diff --git a/src/main.cpp b/src/main.cpp
index fcb57e7..42a27ad 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,9 +1,22 @@
 #include "lexer/lexer.hpp"
 #include "parser/parser.hpp"
 #include <iostream>
+#include <fstream>
+#include <ostream>
+#include <sstream>
 
-int main() {
-    Solstice::Lexer lexer{"(2 + 2) / 5\n(1, 2, 3)"};
+int main(int argc, char** argv) {
+
+    if (argc <= 1) {
+        std::cout << "Usage: " << argv[0] << " <file.sols>" << std::endl;
+        return 1;
+    }
+
+    std::ifstream file{argv[1]};
+    std::stringstream ss;
+    ss << file.rdbuf();
+
+    Solstice::Lexer lexer{ss.str()};
     auto lexed = lexer.lex();
 
     Solstice::Parser parser{lexed};
diff --git a/src/parser/parser.cpp b/src/parser/parser.cpp
index 79b8376..59310d3 100644
--- a/src/parser/parser.cpp
+++ b/src/parser/parser.cpp
@@ -44,6 +44,8 @@ namespace Solstice {
                 return "Expression";
             case NodeType::Tuple:
                 return "Tuple";
+            case NodeType::CodeBlock:
+                return "CodeBlock";
             case NodeType::FunctionBind:
                 return "FunctionBind";
             case NodeType::Bind:
@@ -70,8 +72,8 @@ namespace Solstice {
                 return "GreaterThan";
             case NodeType::LesserThan:
                 return "LesserThan";
-
         }
+        throw std::runtime_error("FIXME Unhandled case in nodeTypeToString");
     }
 
     std::ostream& operator<<(std::ostream& stream, const Node& node) {
@@ -130,6 +132,37 @@ namespace Solstice {
         return node;
     }
 
+    Node Parser::parseActionFunction() {
+        Node node{NodeType::FunctionBind};
+
+        auto previous = getPreviousNode(*context);
+        if (!previous.has_value()) {
+            throw std::runtime_error("expecting function arguments before '->'");
+        }
+
+        // the previous node is either a tuple or expression (for lambda) or a function call (for named function)
+        if (previous->type == NodeType::FunctionCall) {
+            node.type = NodeType::FunctionBind;
+            node.children.push_back(previous->children[0]); // name 
+            node.children.push_back(previous->children[1]); // args 
+        } else if (previous->type == NodeType::Tuple || previous->type == NodeType::Expression) {
+            node.type = NodeType::Lambda;
+            previous->type = NodeType::Tuple; // for consistency's sake 
+            node.children.push_back(*previous);
+        } else {
+            throw std::runtime_error("expecting function arguments before '->'");
+        }
+
+        // process the body for the function 
+        auto body = parseOneNode(Precedence::Root);
+        if (!body.has_value()) {
+            throw std::runtime_error("expecting function body after '->'");
+        }
+        node.children.push_back(*body);
+
+        return node;
+    }
+
     Node Parser::parseExpr(TT type) {
         auto left = getPreviousNode(*context);
         if (!left.has_value()) {
@@ -215,6 +248,52 @@ namespace Solstice {
         return node;
     }
 
+    Node Parser::parseOpenCurly() {
+        Node node{NodeType::CodeBlock};
+
+        for (;;) {
+            while (peek().has_value() && peek()->type == TT::NewLine) {
+                consume();
+            }
+            auto next = peek();
+            if (!next.has_value()) {
+                throw std::runtime_error("unclosed curly bracket");
+            }
+            if (next->type == TT::CloseCurly) {
+                consume();
+                break;
+            }
+
+            Node elem{NodeType::Root};
+            Node* prevContext = context;
+            context = &elem;
+
+            for (;;) {
+                auto t = peek();
+                if (!t.has_value() || t->type == TT::CloseCurly) {
+                    break;
+                }
+                auto n = parseOneNode(Precedence::NewLine);
+                if (!n.has_value()) break;
+                elem.children.push_back(*n);
+            }
+
+            context = prevContext;
+
+            if (elem.children.empty()) {
+                throw std::runtime_error("expecting expression in code block");
+            }
+            node.children.push_back(elem.children.back());
+
+            auto sep = peek();
+            if (!sep.has_value()) {
+                throw std::runtime_error("unclosed parens");
+            }
+        }
+
+        return node;
+    }
+
     Node Parser::parseLiteral() {
         auto current = peek(-1);
         if (!current.has_value()) {
@@ -238,6 +317,17 @@ namespace Solstice {
             throw std::runtime_error("FIXME token with type identifier does not hold an identifier");
         }
 
+        // Check if it's a function call
+        auto next = peek();
+        if (next.has_value() && next->type == TT::OpenParen) {
+            consume();
+            Node argsNode = parseOpenParen();
+            argsNode.type = NodeType::Tuple;
+
+            Node callNode = {NodeType::FunctionCall, {*id, argsNode}};
+            return callNode;
+        }
+
         return Node(*id);
     }
 
@@ -269,6 +359,7 @@ namespace Solstice {
                 return Precedence::Compare;
 
         }
+        throw std::runtime_error("FIXME unhandled node precedence case");
     }
 
     Precedence Parser::getTokenPrecedence(const Token& token) {
@@ -322,6 +413,10 @@ namespace Solstice {
                 return parseExpr(next->type);
             case TT::OpenParen:
                 return parseOpenParen();
+            case TT::Action_Function:
+                return parseActionFunction();
+            case TT::OpenCurly:
+                return parseOpenCurly();
 
             case TT::NewLine:
                 // ignore new line
diff --git a/src/parser/parser.hpp b/src/parser/parser.hpp
index d392041..50e0071 100644
--- a/src/parser/parser.hpp
+++ b/src/parser/parser.hpp
@@ -10,6 +10,7 @@ namespace Solstice {
 
     enum class NodeType {
         Root, Literal, Identifier, Expression, Tuple,
+        CodeBlock,
         FunctionBind, Bind, Set, 
         Lambda, FunctionCall,
         Add, Subtract, Multiply, Divide,