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-rw-r--r--src/__OLD_parcom/first_of.cr40
1 files changed, 0 insertions, 40 deletions
diff --git a/src/__OLD_parcom/first_of.cr b/src/__OLD_parcom/first_of.cr
deleted file mode 100644
index c4077eb..0000000
--- a/src/__OLD_parcom/first_of.cr
+++ /dev/null
@@ -1,40 +0,0 @@
-require "./parser.cr"
-
-module Parcom
- # `FirstOf` is a `Parser` that accepts multiple parsers, and tries to parse
- # with all of them, in order. As soon as one of the parsers succeeds,
- # that parser's result is returned. If none of the parsers are successful,
- # the parsing fails.
- class FirstOf(T, V) < Parser(T, V)
- @p : Parser(T, V)
-
- # Accepts the parsers to use. Raises an `ArgumentError` if
- # no parsers are provided.
- def initialize(ps : Iterable(Parser(T, V)))
- ps_iter = ps.each
- p = ps_iter.next
-
- if p.is_a?(Iterator::Stop)
- raise ArgumentError.new("FirstOf requires atleast one parser, got none")
- end
-
- # Combine all the parsers into one by wrapping them with `Alt`.
- @p = p
-
- loop do
- p = ps_iter.next
- break if p.is_a?(Iterator::Stop)
- @p = @p | p
- end
- end
-
- # Tries to parse with each of the given parsers. Either returns the first
- # successful result or fails if no parsers succeed.
- def parse(tokens : Tokens(T)) : Result(T, V)
- @p.parse(tokens)
- rescue ex : ParserFail
- raise ParserFail.new("FirstOf: #{ex.message}")
- end
- end
-end
-