declaring ranges a-z A-Z 0-9 etc. ?

Is there a way to declare ranges for conditional testing, like [A-Z] or [0-9] ?

Basically I want to turn any char that is not a letter into a space by saying something like:

Code:

if ( c != [A-Z] || c != [a-z]) { c = ' '} return c;

instead of (mostly b/c I get the warning that char constant is too long for its type):

Code:

int replacenum ( int c) { 
  if ( c=='1'||c=='2'||c=='3')||c=='4'||c=='5'||c=='6'||c=='7'||
       c=='8'||c=='9'||c=='0'||c=='`'||c=='~'||c=='!'||c=='@'||
       c=='#'||c=='$'||c=='%'||c=='^'||c=='&'||c=='*'||c=='('||
       c==')'||c=='-'||c=='_'||c=='+'||c=='='||c=='{'||c=='['||
       c=='}'||c==']'||c=='|'||c=='\')//||c==':'||c==';'|| ... )
   {
     c = ' ';
   }
   return c;
}

Have a look in <ctype.h>. You should be able to find some useful functions in there that will make what you are trying to do a lot simpler. In particular, you can use isgraph() and isalpha() to get what you want.