public Ast_Base Parse(ParserState state)
{
var token = Expect(TokenType.Identifier, state);
var ident = ParseIdentifier(token, state);
Ast_Base ast = ident.Type switch
{
AstType.Call => ParseCall(ident, state),
AstType.Keyword => ParseKeyword(ident, state),
AstType.Variable => ParseAssign(ident, state),
AstType.Lambda => ParseLambda(ident, state),
_ => throw new SyntaxError(ident.Token, $"Unhandled ast type ({ident.Type}) found."),
};
return(ast);
}
public Ast_Base ParseAssign(Ast_Base ident, ParserState state)
{
var token = state.GetToken();
var ast = new Ast_Assign(token)
{
Variable = ident as Ast_Variable,
Operand = token,
Expression = ParseExpression(TokenType.Semicolon, state)
};
var ve = state.Scope.VariableExists(ast.Variable.Name);
if (!ve)
{
state.Scope.Variables.Add(ast.Variable);
if (ast.Expression?.Token?.Lexeme.ToString() == Ast_Variable.RecordValue)
{
ast.Variable.SetValue(new Token()
{
Lexeme = Ast_Variable.NewRecordValue, Type = TokenType.TypeRecord
});
}
else if (ast.Expression?.Token?.Lexeme.ToString() == Ast_Variable.ArrayValue)
{
ast.Variable.SetValue(new Token()
{
Lexeme = Ast_Variable.NewArrayValue, Type = TokenType.TypeArray
});
}
else if (ast.Expression?.Token?.Lexeme.ToString() == Ast_Variable.ParamsValue)
{
ast.Variable.SetValue(new Token()
{
Lexeme = Ast_Variable.NewParamsValue, Type = TokenType.TypeParams
});
}
else if (Ast_Expression.Constants.Contains(ast.Expression.Token.Type))
{
ast.Variable.SetValue(ast.Expression.Token);
}
else
{
ast.Variable.SetValue(token: new Token()
{
Lexeme = ast.Expression.ToString(), Type = TokenType.Expression
});
}
}
else
{
var v = state.Scope.GetVariable(ast.Variable.Name);
if (v == null)
{
throw new SyntaxError(token, $"Variable not found {ast.Variable.Name}.");
}
if (v.Value.Type == ValueType.Record && ast.Variable.Index?.Block.Count > 0 && ast.Variable.Index.Block[^ 1].Type == AstType.NewArrayIndex)
{
throw new SyntaxError(token, "Invalid record index, no index was provided.");
}
if ((v.Value.Type == ValueType.Array || v.Value.Type == ValueType.Record || v.Value.Type == ValueType.Params) && ast.Variable.Index == null)
{
var l = ast.Expression.Block[^ 1].Token.Lexeme;