for delphi source code comparsion when comparing with ignoring white chars, here are bug in comparing compiler directives

e.g.

{$DEFINE XYZ} - this is compiler directive

is not same as

{ $DEFINE XYZ} - this is comment

===================

Comments are ignored by the compiler, except when they function as separators (delimiting adjacent tokens) or compiler directives.
There are several ways to construct comments:

{ Text between a left brace and a right brace constitutes a comment. }
(* Text between a left-parenthesis-plus-asterisk and an

asterisk-plus-right-parenthesis also constitutes a comment. *)

// Any text between a double-slash and the end of the line constitutes a comment.

A comment that contains a dollar sign ($) immediately after the opening { or (* is a compiler directive. For example,

{$WARNINGS OFF}

tells the compiler not to generate warning messages.