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-rw-r--r--src/__OLD_parcom/at_least.cr29
1 files changed, 29 insertions, 0 deletions
diff --git a/src/__OLD_parcom/at_least.cr b/src/__OLD_parcom/at_least.cr
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+++ b/src/__OLD_parcom/at_least.cr
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+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
+