Parser Returns Hardcoded AST on Invalid Input

[SAMBA8695]

Description

The parser currently returns a hardcoded AST node (create_num_node(4)) when the first token is not TOKEN_LET.

This causes invalid or unsupported input to silently compile into an incorrect AST instead of producing a syntax error.

Current Code

ASTNode *parse(Token *tokens){
    if(tokens[pos].type == TOKEN_LET){
        ...
        return create_var_declare_node(name, value);
    }
    return create_num_node(4);
}

Current Behavior

Any input that does not begin with let is parsed as the constant value 4.

Example

x + 2;

Produces an AST equivalent to:

4

No error is reported.

Expected Behavior

• The parser should not fabricate AST nodes
• Unsupported or invalid syntax should produce a clear parse error
• Compilation should fail explicitly instead of returning a placeholder value

Suggested Direction

• Remove the hardcoded fallback create_num_node(4)
• Return NULL or a structured parse error
• Add proper error reporting for unsupported top-level syntax