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-rw-r--r--src/__OLD_parcom/any_token.cr18
1 files changed, 18 insertions, 0 deletions
diff --git a/src/__OLD_parcom/any_token.cr b/src/__OLD_parcom/any_token.cr
new file mode 100644
index 0000000..1f65bfc
--- /dev/null
+++ b/src/__OLD_parcom/any_token.cr
@@ -0,0 +1,18 @@
+require "./parser.cr"
+
+module Parcom
+ # `AnyToken` is a `Parser` that consumes exactly one token from
+ # the input stream and returns it.
+ # It fails if the input stream is empty.
+ class AnyToken(T) < Parser(T, T)
+ # Parses the first token in the input, fails if the input is empty.
+ def parse(tokens : Tokens(T)) : Result(T, T)
+ if tokens.empty?
+ raise ParserFail.new("AnyToken: input was empty")
+ else
+ Result.new(tokens[1..], tokens[0])
+ end
+ end
+ end
+end
+