32 lines
999 B
Makefile
32 lines
999 B
Makefile
# $NetBSD: varname-dot-newline.mk,v 1.6 2023/01/26 20:48:18 sjg Exp $
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#
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# Tests for the special .newline variable, which contains a single newline
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# character (U+000A).
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# https://austingroupbugs.net/view.php?id=1549 proposes:
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# > After all macro expansion is complete, when an escaped <newline> is
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# > found in a command line in a makefile, the command line that is executed
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# > shall contain the <backslash>, the <newline>, and the next line, except
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# > that the first character of the next line shall not be included if it is
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# > a <tab>.
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#
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# The above quote assumes that each resulting <newline> character has a "next
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# line", but that's not how the .newline variable works.
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BACKSLASH_NEWLINE:= \${.newline}
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# Check that .newline is read-only
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NEWLINE:= ${.newline}
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.newline= overwritten
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.if ${.newline} != ${NEWLINE}
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. error The .newline variable can be overwritten. It should be read-only.
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.endif
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all:
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@echo 'first${.newline}second'
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@echo 'backslash newline: <${BACKSLASH_NEWLINE}>'
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