Alternative operators and tokens
C source code may be written in any 8-bit character set that includes the MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 14 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE invariant character set, even non-ASCII ones. However, several C operators and punctuators require characters that are outside of the ISO 646 codeset: {, }, [, ], #, \, ^, |, ~. To be able to use character encodings where some or all of these symbols do not exist (such as the German MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 13 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE), there are two possibilities: alternative spellings of operators that use these characters or special combinations of two or three ISO 646 compatible characters that are interpreted as if they were a single non-ISO 646 character.
Operator macros(哋它亢95)
There are alternative spellings for the operators that use non-ISO646 characters, defined in <iso646.h> as macros:
| Defined in header
<iso646.h> | |
| Primary | Alternative |
&& |
and (operator macro) |
&= |
and_eq (operator macro) |
& |
bitand (operator macro) |
| |
bitor (operator macro) |
~ |
compl (operator macro) |
! |
not (operator macro) |
!= |
not_eq (operator macro) |
|| |
or (operator macro) |
|= |
or_eq (operator macro) |
^ |
xor (operator macro) |
^= |
xor_eq (operator macro) |
The characters & and ! are invariant under ISO-646, but alternatives are provided for the operators that use these characters anyway to accommodate even more restrictive historical charsets.
There is no alternative spelling (such as eq) for the equality operator == because the character = was present in all supported charsets.
Alternative tokens(哋它亢95)
The following alternative tokens are part of the core language, and, in all respects of the language, each alternative token behaves exactly the same as its primary token, except for its spelling (the MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 12 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE can make the spelling visible). The two-letter alternative tokens are sometimes called "digraphs" (even though it is four letters long %:%: is also considered a digraph).
| Primary | Alternative |
|---|---|
{ |
<%
|
|
%>
|
[ |
<:
|
] |
:>
|
# |
%:
|
## |
%:%:
|
Trigraphs (removed in 哋它亢23)
The following three-character groups (trigraphs) are MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 10 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE, and each appearance of a trigraph is replaced by the corresponding primary character:
| Primary | Trigraph |
|---|---|
{ |
??<
|
|
??>
|
[ |
??(
|
] |
??)
|
# |
??=
|
\ |
??/
|
^ |
??'
|
| |
??!
|
~ |
??-
|
Because trigraphs are processed early, a comment such as // Will the next line be executed?????/ will effectively comment out the following line, and the string literal such as "What's going on??!" is parsed as "What's going on|".
Example
Demonstrates alternative operator spellings from the <iso646.h> as well as use of digraphs and trigraphs. If command line arguments contain spaces they should be wrapped in the quotation marks, e.g., "Third World!".
%:include <stdio.h> %:include <stdlib.h> ??=include <iso646.h> int main(int argc, char** argv) ??< if (argc > 1 and argv<:1:> not_eq MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 09 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE) <% MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 08 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("Hello %s??/n", argv<:1:>); %> else <% MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 07 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE("Hello %s??/n", argc? argv??(42??'42??) : __FILE__); %> return EXIT_SUCCESS; ??>
MYMEMORY WARNING: YOU USED ALL AVAILABLE FREE TRANSLATIONS FOR TODAY. NEXT AVAILABLE IN 09 HOURS 13 MINUTES 05 SECONDS VISIT HTTPS://MYMEMORY.TRANSLATED.NET/DOC/USAGELIMITS.PHP TO TRANSLATE MORE
Hello ./a.out