Help: How can I get error message as a string? Thanks.

 
I tried to use ErrorDescription(GetLastError()) to get the error message, but the programme couldn't be complied successfully and it said "function is defined". So how can I get that? Thanks for help.
 

#include <stdlib.mqh>

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Print(ErrorDescription(GetLastError()) ;

 

Thanks for your help. Now it works.

Reason: