22 lines
659 B
Perl
22 lines
659 B
Perl
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/* recurs.t: recursive macro */
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/* The sample posted to comp.std.c by B. Stroustrap. */
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#define NIL(xxx) xxx
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#define G_0(arg) NIL(G_1)(arg)
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#define G_1(arg) NIL(arg)
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G_0(42)
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/*
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* Note by kmatsui:
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* There are two interpretations on the Standard's specification.
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* (1) This macro should be expanded to 'NIL(42)'.
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* (2) This macro should be expanded to '42'.
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* The Standard's wording seems to justify the (1).
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* GCC, Visual C++ and other major implementations, however, expand
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* this macro as (2).
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* MCPP V.2.4.1 or later of Standard mode expands this as (1) by default,
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* and expands as (2) when invoked with -@compat option.
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*/
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