stderr

first-interpreter/src/execute.c

@@ -62,7 +62,7 @@ Environment insert(char* name, int n, Memory memory, Environment env) {
         Environment new_env = (Environment) {.next = cell};
         return new_env;
     }
-    printf("Error: out of memory.");
+    fprintf(stderr, "Error: out of memory.");
     exit(1);
 }
 
@@ -93,7 +93,7 @@ int eval_expr(Expr expr, Memory memory, Environment env) {
     case VARIABLE: {
         int* result = lookup(expr.data.variable, memory, env);
         if (result == NULL) {
-            printf("Error: variable not found '%s'\n", expr.data.variable);
+            fprintf(stderr, "Error: variable not found '%s'\n", expr.data.variable);
             exit(1);
         } else {
             return *result;
@@ -106,7 +106,7 @@ int eval_expr(Expr expr, Memory memory, Environment env) {
                 printf("%d\n", arg);
                 return 0;
             } else {
-                printf("Error: print expects a single argument.\n");
+                fprintf(stderr, "Error: print expects a single argument.\n");
                 exit(1);
             }
         }
@@ -116,7 +116,7 @@ int eval_expr(Expr expr, Memory memory, Environment env) {
                 int arg2 = eval_expr(((Expr*)expr.data.function.args.elements)[1], memory, env);
                 return arg1 + arg2;
             } else {
-                printf("Error: negate expects a single argument.\n");
+                fprintf(stderr, "Error: negate expects a single argument.\n");
                 exit(1);
             }
         }
@@ -125,7 +125,7 @@ int eval_expr(Expr expr, Memory memory, Environment env) {
                 int arg = eval_expr(((Expr*)expr.data.function.args.elements)[0], memory, env);
                 return 0 - arg;
             } else {
-                printf("Error: negate expects a single argument.\n");
+                fprintf(stderr, "Error: negate expects a single argument.\n");
                 exit(1);
             }
         }

first-interpreter/src/lex.c

@@ -79,7 +79,7 @@ TokenArray lex(char* txt, unsigned length) {
                 tokens[tokens_index] = (Token){ .tag = INTEGER, .data.integer = integer, };
                 ++tokens_index;
             } else {
-                printf("unexpected character '%c'", txt[txt_index]);
+                fprintf(stderr, "unexpected character '%c'", txt[txt_index]);
             }
         }
         }

first-interpreter/src/parse.c

@@ -21,7 +21,7 @@ int maybe_parse_token(TokenArray tokens, unsigned* tokens_index, TokenTag tag) {
 
 void parse_token(TokenArray tokens, unsigned* tokens_index, TokenTag tag) {
     if (!(maybe_parse_token(tokens, tokens_index, tag))) {
-        printf("Parse error: unexpected token. Expected %d\n", tag);
+        fprintf(stderr, "Parse error: unexpected token. Expected %d\n", tag);
         exit(1);
     }
 }
@@ -31,12 +31,12 @@ char* parse_identifier(TokenArray tokens, unsigned* tokens_index) {
         Token token = tokens.tokens[*tokens_index];
         ++(*tokens_index);
         if (token.tag != IDENTIFIER) {
-            printf("Parse error: got wrong token: %d, expected IDENTIFIER\n", token.tag);
+            fprintf(stderr, "Parse error: got wrong token: %d, expected IDENTIFIER\n", token.tag);
             exit(1);
         }
         return token.data.identifier;
     } else {
-        printf("Parse error: unexpected end of text.\n");
+        fprintf(stderr, "Parse error: unexpected end of text.\n");
         exit(1);
     }
 }
@@ -54,6 +54,7 @@ Expr parse_function(TokenArray tokens, unsigned* tokens_index, char* name) {
         }
     }
     parse_token(tokens, tokens_index, CLOSEPAREN);
+
     return (Expr) {
         .tag = FUNCTION,
         .data.function = {
@@ -88,11 +89,11 @@ Expr parse_expr(TokenArray tokens, unsigned* tokens_index) {
             }
         }
         default:
-            printf("Parse error: got wrong token: %d, expected IDENTIFIER or INTEGER\n", token.tag);
+            fprintf(stderr, "Parse error: got wrong token: %d, expected IDENTIFIER or INTEGER\n", token.tag);
             exit(1);
         }
     } else {
-        printf("Parse error: unexpected end of text.\n");
+        fprintf(stderr, "Parse error: unexpected end of text.\n");
         exit(1);
     }
 }
@@ -102,21 +103,24 @@ StmtArray parse_block(TokenArray tokens, unsigned* tokens_index);
 Stmt parse_stmt(TokenArray tokens, unsigned* tokens_index) {
     char* identifier = parse_identifier(tokens, tokens_index);
 
+	// While
     if (is_while(identifier)) {
-        Expr expr = parse_expr(tokens, tokens_index);
+        Expr condition = parse_expr(tokens, tokens_index);
-
         StmtArray block = parse_block(tokens, tokens_index);
+
         return (Stmt) {
             .tag = WHILE,
             .data.While = {
-                .condition = expr,
+                .condition = condition,
                 .block = {
                     .elements = block.stmts,
                     .length = block.length,
                 },
             },
         };
-    } else if (maybe_parse_token(tokens, tokens_index, EQUALS)) {
+    }
+	// Set
+	else if (maybe_parse_token(tokens, tokens_index, EQUALS)) {
         Expr expr = parse_expr(tokens, tokens_index);
 
         return (Stmt) {
@@ -126,7 +130,9 @@ Stmt parse_stmt(TokenArray tokens, unsigned* tokens_index) {
                 .expr = expr,
             },
         };
-    } else {
+    }
+	// Expression
+	else {
         Expr expr = parse_function(tokens, tokens_index, identifier);
 
         return (Stmt) {