if statements work

plasma_parser.py

@@ -4,9 +4,9 @@ from typing import Callable
 from enum import Enum, auto
 
 from AST import Statement, Expression, Program
-from AST import ExpressionStatement, AssignmentStatement, FunctionStatement, ReturnStatement, BlockStatement, ReassignStatement
+from AST import ExpressionStatement, AssignmentStatement, FunctionStatement, ReturnStatement, BlockStatement, ReassignStatement, IfStatement
 from AST import InfixExpression
-from AST import IntegerLiteral, FloatLiteral, IdentifierLiteral
+from AST import IntegerLiteral, FloatLiteral, IdentifierLiteral, BooleanLiteral
 
 class PrecedenceType(Enum):
 	P_LOWEST = 0
@@ -25,7 +25,13 @@ PRECEDENCES: dict[TokenType, PrecedenceType] = {
 	TokenType.ASTERISK: PrecedenceType.P_PRODUCT,
 	TokenType.SLASH: PrecedenceType.P_PRODUCT,
 	TokenType.MODULUS: PrecedenceType.P_PRODUCT,
-	TokenType.POW: PrecedenceType.P_EXPONENT
+	TokenType.POW: PrecedenceType.P_EXPONENT,
+	TokenType.EQ_EQ: PrecedenceType.P_EQUALS,
+	TokenType.NOT_EQ: PrecedenceType.P_EQUALS,
+	TokenType.LT: PrecedenceType.P_LESSGREATER,
+	TokenType.GT: PrecedenceType.P_LESSGREATER,
+	TokenType.LT_EQ: PrecedenceType.P_LESSGREATER,
+	TokenType.GT_EQ: PrecedenceType.P_LESSGREATER
 }
 
 class Parser:
@@ -38,22 +44,27 @@ class Parser:
 		self.peek_token: Token = None
 
 		self.prefix_parse_functions: dict[Token, Callable] = { # -1
-
 			TokenType.IDENT: self.__parse_identifier,
 			TokenType.INT: self.__parse_int_literal,
 			TokenType.FLOAT: self.__parse_float_literal,
-			TokenType.LPAREN: self.__parse_grouped_expression
-
+			TokenType.LPAREN: self.__parse_grouped_expression,
+			TokenType.IF: self.__parse_if_statement,
+			TokenType.TRUE: self.__parse_boolean,
+			TokenType.FALSE: self.__parse_boolean,
 		} 
 		self.infix_parse_functions: dict[Token, Callable] = { # 5 + 5
-
 			TokenType.PLUS: self.__parse_infix_expression,
 			TokenType.MINUS: self.__parse_infix_expression,
 			TokenType.SLASH: self.__parse_infix_expression,
 			TokenType.ASTERISK: self.__parse_infix_expression,
 			TokenType.POW: self.__parse_infix_expression,
-			TokenType.MODULUS: self.__parse_infix_expression
-
+			TokenType.MODULUS: self.__parse_infix_expression,
+			TokenType.EQ_EQ: self.__parse_infix_expression,
+			TokenType.NOT_EQ: self.__parse_infix_expression,
+			TokenType.LT: self.__parse_infix_expression,
+			TokenType.GT: self.__parse_infix_expression,
+			TokenType.LT_EQ: self.__parse_infix_expression,
+			TokenType.GT_EQ: self.__parse_infix_expression,
 		} 
 
 		self.__next_token()
@@ -229,6 +240,30 @@ class Parser:
 			self.__next_token()
 
 		return block_stmt
+	
+	def __parse_if_statement(self) -> IfStatement:
+		condition: Expression = None
+		consequence: BlockStatement = None
+		alternative: BlockStatement = None
+
+		self.__next_token()
+
+		condition = self.__parse_expression(PrecedenceType.P_LOWEST)
+
+		if not self.__expect_peek(TokenType.LBRACE):
+			return None
+		
+		consequence = self.__parse_block_statement()
+
+		if self.__peek_token_is(TokenType.UNLESS):
+			self.__next_token()
+
+			if not self.__expect_peek(TokenType.LBRACE):
+				return None
+			
+			alternative = self.__parse_block_statement()
+
+		return IfStatement(condition, consequence, alternative)
 	# endregion
 
 	# region Expression Methods
@@ -297,4 +332,7 @@ class Parser:
 			return None
 		
 		return float_lit
+	
+	def __parse_boolean(self) -> BooleanLiteral:
+		return BooleanLiteral(value=self.__current_token_is(TokenType.TRUE))
 	# endregion