Second rewrite attempt, this one should work, monkaS

1 files changed, 37 insertions, 0 deletions

diff --git a/src/__OLD_parcom/between.cr b/src/__OLD_parcom/between.cr
new file mode 100644
index 0000000..05519e4
--- /dev/null
+++ b/src/__OLD_parcom/between.cr
@@ -0,0 +1,37 @@
+require "./parser.cr"
+require "./map.cr"
+require "./exactly.cr"
+require "./at_most.cr"
+
+module Parcom
+  # `Between` is a `Parser` that tries to parse with another parser a number
+  # of times within a specified range. The results of each successful parse
+  # are returned in an array. If the number of successful parses is out of
+  # the lower bound of the range, the parser fails. If the number of successful
+  # parses reaches thhe upper bound of the range, the parsing stops, even if it
+  # is possible to keep parsing.
+  class Between(T, V) < Parser(T, Array(V))
+    @p : Map(T, {Array(V), Array(V)}, Array(V))
+
+    # Accepts the lower and upper bounds for the number of parsing attempts,
+    # as well as the parser to use. This method works the same way whether or
+    # not the larger value is passed first or second. If a negative int value
+    # is given for either parameter, it is treated as `0`.
+    # TODO: Overload to allow for Range objects.
+    def initialize(i : Int, j : Int, p : Parser(T, V))
+      lower = i < j ? i : j
+      upper = (i - j).abs
+      @p = (Exactly.new(lower, p) + AtMost.new(upper, p)).map do |tup|
+        tup[0] + tup[1]
+      end
+    end
+
+    # Tries to parse a numebr of times within the given range.
+    def parse(tokens : Tokens(T)) : Result(T, Array(V))
+      @p.parse(tokens)
+    rescue ex : ParserFail
+      raise ParserFail.new("Between: #{ex.message}")
+    end
+  end
+end
+