Second rewrite attempt, this one should work, monkaS

1 files changed, 29 insertions, 0 deletions

diff --git a/src/__OLD_parcom/at_least.cr b/src/__OLD_parcom/at_least.cr
new file mode 100644
index 0000000..2fb8dcf
--- /dev/null
+++ b/src/__OLD_parcom/at_least.cr
@@ -0,0 +1,29 @@
+require "./parser.cr"
+require "./map.cr"
+require "./exactly.cr"
+
+module Parcom
+  # `AtLeast` is a `Parser` that tries to parser with another parser
+  # a specific number of times. The results of each successful parse
+  # are returned in an array. If the number of successes is less than
+  # the specified number, the parser fails.
+  class AtLeast(T, V) < Parser(T, Array(V))
+    @p : Map(T, {Array(V), Array(V)}, Array(V))
+
+    # Accepts the number of parsing attempts, and the parser to use.
+    # If a negative int is given, it is treated as if it were 0.
+    def initialize(i : Int, p : Parser(T, V))
+      @p = (Exactly.new(i, p) + Many.new(p)).map do |tup|
+        tup[0] + tup[1]
+      end
+    end
+
+    # Tries to parse the given number of times, or more.
+    def parse(tokens : Tokens(T)) : Result(T, Array(V))
+      @p.parse(tokens)
+    rescue ex : ParserFail
+      raise ParserFail.new("AtLeast: #{ex.message}")
+    end
+  end
+end
+