lib/core: Added packing methods to `Text`

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>

diff --git a/lib/core/text/abstract_text.nit b/lib/core/text/abstract_text.nit
index e0e8dda..7fb65ee 100644 (file)
--- a/lib/core/text/abstract_text.nit
+++ b/lib/core/text/abstract_text.nit
@@ -1095,6 +1095,39 @@ abstract class Text
                end
        end
 
+       # Packs the content of a string in packs of `ln` chars.
+       # This variant ensures that only the last element might be smaller than `ln`
+       #
+       # ~~~nit
+       # var s = "abcdefghijklmnopqrstuvwxyz"
+       # assert s.pack_l(4) == ["abcd","efgh","ijkl","mnop","qrst","uvwx","yz"]
+       # ~~~
+       fun pack_l(ln: Int): Array[Text] do
+               var st = 0
+               var retarr = new Array[Text].with_capacity(length / ln + length % ln)
+               while st < length do
+                       retarr.add(substring(st, ln))
+                       st += ln
+               end
+               return retarr
+       end
+
+       # Packs the content of a string in packs of `ln` chars.
+       # This variant ensures that only the first element might be smaller than `ln`
+       #
+       # ~~~nit
+       # var s = "abcdefghijklmnopqrstuvwxyz"
+       # assert s.pack_r(4) == ["ab","cdef","ghij","klmn","opqr","stuv","wxyz"]
+       # ~~~
+       fun pack_r(ln: Int): Array[Text] do
+               var st = length
+               var retarr = new Array[Text].with_capacity(length / ln + length % ln)
+               while st >= 0 do
+                       retarr.add(substring(st - ln, ln))
+                       st -= ln
+               end
+               return retarr.reversed
+       end
 end
 
 # All kinds of array-based text representations.