const AST *ast_str(const loc_t &loc, std::vector<ASTChar> *chars, bool icase)
{
    AST *ast = new AST(loc, AST::STR);
    ast->str.chars = chars;
    ast->str.icase = icase;
    return ast;
}
const AST *ast_str(const loc_t &loc, std::vector<ASTChar> *chars, bool icase)
{
    AST *ast = new AST(loc, AST::STR);
    ast->str.chars = chars;
    ast->str.icase = icase;
    return ast;
}