summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/metapost/base/string.mp
blob: dbd19592f96346b1f95aa57d2a9b7108cdfcd86e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
% $Id: string.mp,v 1.2 2004/09/19 21:47:11 karl Exp $
% Public domain.

% String manipulation routines for MetaPost
% It is harmless to input this file more than once.


vardef isdigit primary d =
  ("0"<=d)and(d<="9") enddef;


% Number of initial characters of string s where `c <character>' is true
vardef cspan(expr s)(text c) =
  0
  for i=1 upto length s:
    exitunless c substring (i-1,i) of s;
    + 1
  endfor
enddef;


% String s is composed of items separated by white space.  Lop off the first
% item and the surrounding white space and return just the item.
vardef loptok suffix s =
  save t, k;
  k = cspan(s," ">=);
  if k>0: s:=substring(k,infinity) of s; fi
  k := cspan(s," "<);
  string t;
  t = substring (0,k) of s;
  s := substring (k,infinity) of s;
  s := substring (cspan(s," ">=),infinity) of s;
  t
enddef;