Add switch functionality

compiler.py

@@ -269,6 +269,15 @@ def compile(opcodes, c_filename, table):
         # If opcode is of type continue then generate continue statement
         elif opcode.type == "continue":
             code += "\tcontinue;\n"
+        # If opcode is of type switch then generate switch statement
+        elif opcode.type == "switch":
+            code += "\tswitch(" + opcode.val + ") {\n";
+        # If opcode is of type case then generate case statement
+        elif opcode.type == "case":
+            code += "\tcase " + opcode.val + ":\n"
+        # If opcode is of type default then generate default statement
+        elif opcode.type == "default":
+            code += "\tdefault:\n"
 
         outside_code, ccode = compile_func_main_code(
             outside_code, ccode, outside_main, code

lexical_analyzer.py

@@ -39,6 +39,9 @@ def is_keyword(value):
         "continue",
         "input",
         "exit",
+        "switch",
+        "case",
+        "default"
     ]
 
 
@@ -353,6 +356,11 @@ def lexical_analyze(filename, table):
                 tokens.append(Token("less_than_equal", "", line_num))
                 i += 2
 
+        # Identifiying colon token
+        elif source_code[i] == ':':
+            tokens.append(Token("colon", "", line_num))
+            i += 1
+
         # Otherwise increment the index
         else:
             i += 1

simc.py

@@ -33,5 +33,8 @@
     # Get opcodes from parser
     op_codes = parse(tokens, table)
 
+    for op_code in op_codes:
+        print(op_code)
+
     # Compile to C code
     compile(op_codes, c_filename, table)

simc_parser.py

@@ -964,6 +964,30 @@ def exit_statement(tokens, i, table, func_ret_type):
 
     return OpCode("exit", op_value[:-1]), i, func_ret_type
 
+def switch_statement(tokens, i, table, func_ret_type):
+
+    check_if(tokens[i].type, "left_paren", "Expected ( after switch", tokens[i].line_num)
+
+    op_value, _, i, func_ret_type = expression(
+        tokens, i+1, table, "Expected expression inside switch statement", func_ret_type=func_ret_type
+    )
+
+    check_if(tokens[i-1].type, "right_paren", "Expected ) after expression in switch", tokens[i-1].line_num)
+
+    check_if(tokens[i+1].type, "left_brace", "Expected { after switch statement", tokens[i].line_num)
+
+    return OpCode("switch", op_value[:-1], ""), i+1, func_ret_type
+
+def case_statement(tokens, i, table, func_ret_type):
+
+    op_value, _, i, func_ret_type = expression(
+        tokens, i, table, "Expected expected expression after case", expect_paren=False, func_ret_type=func_ret_type
+    )
+
+    check_if(tokens[i].type, "colon", "Expected : after case in switch statement", tokens[i].line_num)
+
+    return OpCode("case", op_value, ""), i+1, func_ret_type
+
 def parse(tokens, table):
     """
     Parse tokens and generate opcodes
@@ -1127,6 +1151,19 @@ def parse(tokens, table):
         elif tokens[i].type == "continue":
             op_codes.append(OpCode("continue", "", ""))
             i += 1
+        # If token is of type switch then generate switch opcode
+        elif tokens[i].type == "switch":
+            switch_opcode, i, func_ret_type = switch_statement(tokens, i+1, table, func_ret_type)
+            op_codes.append(switch_opcode)
+        # If token is of type case then generate case opcode
+        elif tokens[i].type == "case":
+            case_opcode, i, func_ret_type = case_statement(tokens, i+1, table, func_ret_type)
+            op_codes.append(case_opcode)
+        # If token is of type default then generate default opcode
+        elif tokens[i].type == "default":
+            check_if(tokens[i+1].type, "colon", "Expected : after default statement in switch", tokens[i+1].line_num)
+            op_codes.append(OpCode("default", "", ""))
+            i += 2
         # Otherwise increment the index
         else:
             i += 1

test.c

@@ -1,13 +1,19 @@
 #include <stdio.h>
 
-int sum(int a, int b) {
-
-	return a + b;
-}
-
 int main() {
-	int hello = sum(1, 2);
-	printf("The sum = %d", hello);
-	exit(0);
+	int a = 1;
+	int b = 2;
+	switch(a + b) {
+	case 1:
+	printf("Hello");
+	break;
+	case 2:
+	printf("World");
+	break;
+	default:
+	printf("Default");
+	break;
+	}
+
 	return 0;
 }

test.simc

@@ -1,9 +1,16 @@
-fun sum(a, b) {
-  return a + b
-}
-
 MAIN
-  var hello = sum(1, 2)
-  print("The sum = {hello}")
-  exit (0)
+  var a = 1
+  var b = 2
+
+  switch(a + b) {
+    case 1:
+      print("Hello")
+      break
+    case 2:
+      print("World")
+      break
+    default:
+      print("Default")
+      break
+  }
 END_MAIN