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169516ffc0
as a parameter and the funcret is also passed as parameter. Because in that
case both are pointing to the same memory location
git-svn-id: trunk@10159 -
38 lines
734 B
ObjectPascal
38 lines
734 B
ObjectPascal
{$ifdef fpc}{$mode objfpc}{$H+}{$endif}
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const buf: array[0..5] of char = 'abcdef';
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function foo(const a: string): string;
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begin
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SetLength(result, 6);
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Move(buf, result[1], sizeof(buf));
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if a <> '1234567890' then
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begin
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writeln('Failed: ', a);
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Halt(1);
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end
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else
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writeln('ok');
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end;
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procedure test_proc(var a: string);
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var
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s: string;
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begin
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{ Don't call UniqueString(s) here because it makes the compiler assume
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that address of s is taken, and assignment s := foo(s) is not optimized }
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s := a; // refcount=2
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a := 'whatever'; // modify source -> s.refcount becomes 1
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writeln('before: ', s);
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s := foo(s);
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writeln(s);
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end;
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var
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s: string;
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begin
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s := '1234567890';
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UniqueString(s);
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test_proc(s);
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end.
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