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NAME ==== Raku port of Perl's length() built-in SYNOPSIS ======== use P5length; # exports length() say length("foobar"); # 6 say length(Str); # Str $_ = "foobar"; say length; # 6 DESCRIPTION =========== This module tries to mimic the behaviour of Perl's `length` built-in as closely as possible in the Raku Programming Language. ORIGINAL PERL 5 DOCUMENTATION ============================= length EXPR length Returns the length in characters of the value of EXPR. If EXPR is omitted, returns the length of $_. If EXPR is undefined, returns "undef". This function cannot be used on an entire array or hash to find out how many elements these have. For that, use "scalar @array" and "scalar keys %hash", respectively. Like all Perl character operations, length() normally deals in logical characters, not physical bytes. For how many bytes a string encoded as UTF-8 would take up, use "length(Encode::encode_utf8(EXPR))" (you'll have to "use Encode" first). See Encode and perlunicode. PORTING CAVEATS =============== Characters vs codepoints ------------------------ Since the Perl documentation mentions `characters` rather than codepoints, `length` will return the number of characters, as seen using Normalization Form Grapheme (NFG). Handling of type objects ------------------------ `length` in Perl is supposed to return `undef` when given `undef`. Since undefined values are type objects in Raku, and it looks like `length` is simply returning what it was given in the undefined case, it felt appropriate to simply return the given type object rather than `Nil`. $_ no longer accessible from caller's scope ------------------------------------------- In future language versions of Raku, it will become impossible to access the `$_` variable of the caller's scope, because it will not have been marked as a dynamic variable. So please consider changing: length; to either: length($_); or, using the subroutine as a method syntax, with the prefix `.` shortcut to use that scope's `$_` as the invocant: .&length; AUTHOR ====== Elizabeth Mattijsen <[email protected]> Source can be located at: https://github.com/lizmat/P5length . Comments and Pull Requests are welcome. COPYRIGHT AND LICENSE ===================== Copyright 2018-2020 Elizabeth Mattijsen Re-imagined from Perl as part of the CPAN Butterfly Plan. This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.