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-rw-r--r--src/__OLD_parcom/exactly.cr28
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diff --git a/src/__OLD_parcom/exactly.cr b/src/__OLD_parcom/exactly.cr
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+require "./parser.cr"
+
+module Parcom
+ # `Exactly` is a `Parser` that tries to parse 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
+ # OR greater than the specified number, the parser fails.
+ class Exactly(T, V) < Parser(T, Array(V))
+ @p : Sequence(T, 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))
+ i = i.negative? ? 0 : i
+ # put `i` copies of `p` into an array
+ ps = ([p] of Parser(T, V)) * i
+ @p = Sequence.new(ps)
+ end
+
+ # Tries to parse the given number of times.
+ def parse(tokens : Tokens(T)) : Result(T, Array(V))
+ @p.parse(tokens)
+ rescue ex : ParserFail
+ raise ParserFail.new("Exactly: #{ex.message}")
+ end
+ end
+end
+