Operator is not overloaded: not "AnsiString"?

[ShungFeng]

Hi! 

I'm trying to compare two strings, but I get the error:

Operator is not overloaded: not "AnsiString"

Code: Pascal  [Select][+][-]

1. var
2.   a, b, c: string;
3. begin
4.   b := c + 'text'
5.  
6.   if not a = b then
7.     DoSomething();
8. end;

How can I fix this error?

[bytebites]

Code: Pascal  [Select][+][-]

1. if not (a = b) then
2.     DoSomething();

or

Code: Pascal  [Select][+][-]

1. if  a <> b then
2.     DoSomething();

[ShungFeng]

Thank you! The first one worked.

[uart]

but I get the error: "Operator is not overloaded: not "AnsiString"

The reason your code fails is that "not" is a higher precedence logical operator than "=".

So Pascal thinks that you are trying to do: if not (a) = b then ..., and is complaining that it doesn't know how to do the "not" of a string.

See: https://www.freepascal.org/docs-html/ref/refch12.html

[Remy Lebeau]

So Pascal thinks that you are trying to do: if not (a) = b then ...

I think you mean: if (not a) = b then ...