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How to split a string into an array in PostScript

What is the easiest way to split a string into an array by a given character? For example, creating an array of words by splitting over space; or even creating an array of all characters in a string.

The only method I can think of is to use searchin a loop. Since all languages ​​have a function for this purpose, I am afraid that I lack a function in PostScriptfor this.

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You are on the right track with the help of an operator search. It is designed to search and match text strings. Here is a brief description of the statement searchfound in the PostScript Language Reference :

search   string seek search post match pre true (if found)  
         string false (if not found)  

         looks for the first occurrence of the string seek within string and  
         returns results of this search on the operand stack. The topmost   
         result is a boolean that indicates if the search succeeded.  

         If search finds a subsequence of string whose elements are equal   
         to the elements of seek, it splits string into three segments:   
         pre, the portion of string preceding the match; match, the portion  
         of string that matches seek; and post, the remainder of string. It  
         then pushes the string objects post, match, and pre on the operand   
         stack, followed by the boolean true. All three of these strings are  
         substrings sharing intervals of the value of the original string.  

         If search does not find a match, it pushes the original string  
         and the boolean false.  

         Example:  

             (abbc) (ab) search ==> (bc) (ab) ( ) true  
             (abbc) (bb) search ==> (c) (bb) (a) true  
             (abbc) (bc) search ==> () (bc) (ab) true  
             (abbc) (B) search ==> (abbc) false
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%!

%(string) (delimiter)  split  [(s)(t)(r)(i)(n)(g)]
/split {              % str del
    [ 3 1 roll        % [ str del
    {                 % [ ... str del
        search {      % [ ... post match pre
            3 1 roll   % [ ... pre post match  %ie. [ ... pre str' del
        }{            % [ ... str
            exit       % [ ... str  %% break-from-loop
        }ifelse
    }loop             % [ ...
    ]                 % [ ... ]
} def

(string of words separated by spaces)( )split ==
%-> [(string) (of) (words) (separated) (by) (spaces)]

(string.of.words.separated.by.dots)(.)split ==
%-> [(string) (of) (words) (separated) (by) (dots)]
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