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Changes between Version 1 and Version 2 of IfDirective

IfDirective

v1	v2
3	3	This does not describe an existing feature. It's place to jot down notes for my idea of an @if directive and related features.
4	4
5		== ~~Introduc~~tion ==
	5	== Motivation ==
6	6
7		Conditional inclusion of source code is needed in some circumstances. Some of the better known ones are:
	7	Conditional inclusion of source code (aka "conditional compilation") is needed in some circumstances. Some of the better known ones are:
8	8	* Adjusting for the back-end (CLR, JVM)
9	9	* Demo vs. Production
…	…
11	11	* Adjusting for compiler options (-include-tests, etc.)
12	12
	13	Other languages including C# (#if, #define) and D (static if, version, ...) have condition compilation features which are taken advantage of by their communities.
	14
	15	== Syntax ==
	16
	17	General, full form:
	18	{{{
	19	#!cobra
	20	@if <condition>
	21	<code>
	22	@else if <condition>
	23	<code>
	24	@else
	25	<code>
	26	}}}
	27	But "@else if" and "@else" are optional and "@else if" can be repeated.
	28
	29	== Defining Symbols ==
	30
	31	{{{
	32	cobra -define:FOO -define:FOO=bar ...
	33	}}}
	34
	35	Or in code:
	36	{{{
	37	#!cobra
	38	@define FOO
	39	@define FOO = 'bar'
	40	}}}
	41
	42	== Automatic Symbols ==
	43
	44	CLR, CLR20, CLR40, JVM, JVM16, JVM17, JVM18, OBJC, DOTNET, MONO, WINDOWS, UNIX, MAC, ASSERTS, TESTS, CONTRACTS, DEBUG, DST, ERT
	45
	46	... or we could go all lower case:
	47
	48	clr, jvm, objc, dotnet, etc.
	49
	50
13	51	== See Also ==
14	52
	53	* Discussion at http://cobra-language.com/forums/viewtopic.php?f=4&t=966
15	54	* CompilerDirectives
16	55	* LanguageTopics