Three-character groups for standard C languages and separators for alternate spellings

StandardCThe language includes a set of three-character groups thatClanguage programs can only be usedISO 646-1083The invariant code set is written, which is seven bitsASCIIA subset of the code sets that are common to many non-English-language character sets. The three-character group starts with two consecutive question marks, see. StandardCThe language also provides some token of the re-spelling and defines some operators for the macro replacement header file<iso646.h>, but unlike a three-character group, these substitutions cannot be recognized in string constants and character-type constants.

the conversion of a three-character group in the source program occurs before the lexical analysis (converted to a token) and before the escape character is recognized in the string constant and character type constants. StandardClanguage can only recognize the above9a three-character group, all other character sequences, such as?? &) does not convert. The new escape character\?can be used to prevent the interpretation of a sequence of characters similar to a three-character group.

to help programmers use a language that does not have some American or English charactersI/Odevice, replacing spelling<%,%>,<:,:>,%:,%:%:equivalent to separators, respectively{,},[,],#,##, see.

In the following example, the delimiter uses two forms of the same result:

MAIN.C #include <stdio.h> #define SEASON (SEASON) "SEASON is:" #season #define MONTH "month is:"%:month #d Efine adhere (one, b) one# #two #define LINK (one, both) One%:%:two int main (void) {     char arr[] = {' A ', ' B '};     Char arr2<::> = <% ' C ', ' d '%>;     printf ("%c,%c\n", arr[0], arr[1]); A, B     printf ("%c,%c\n", Arr2<:0:>, arr2<:1:>);//C, D      printf ("%s\n", SEASON ("Summer"));// Season is: "Summer"     printf ("%s\n", Month ("April"));//month ID: "April"     printf ("%d\n", Adhere (1, 2));//12< c13/>printf ("%d\n", LINK (3, 4));     return 0;}

Three-character groups for standard C languages and separators for alternate spellings