1 files changed, 31 insertions, 0 deletions
diff --git a/Master/texmf-dist/metapost/base/string.mp b/Master/texmf-dist/metapost/base/string.mp
new file mode 100644
index 00000000000..2cf5a7ff4dd
--- /dev/null
+++ b/Master/texmf-dist/metapost/base/string.mp
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+% 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;