Re^3: PerlIO::Layers 0.011 fails to build in macOS 10.13.3

with your little c-program:

gcc -DVER="0.1" -E try.c

does the preprocessor pass and expands FOO to:

printf("%s\n", "" 0.1 "")
[download]

and

gcc -DVER="\"0.1\"" -E try.c

expands it to:

printf("%s\n", "" "0.1" "")
[download]

so, whereas

printf("%s\n", 0.1)
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would have caused just a warning at compile time and a crash later,

printf("%s\n", "" 0.1 "")
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causes an error right away

and

printf("%s\n", "" "0.1" "")
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is legitimate.

bliako

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Re^4: PerlIO::Layers 0.011 fails to build in macOS 10.13.3 by syphilis (Archbishop) on Mar 29, 2018 at 01:07 UTC
`printf("%s\n", "" "0.1" "")` didn't immediately look like valid C to me (and it's not valid perl). But C does allow that type of concatenation - whereas I guess perl doesn't really need to. Even in assignment one can do `char *x = "hello" "0.01" "world";` Cheers, Rob	[reply] [d/l] [select]