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IO::CatHandle::AutoLines zef:raku-community-modules last updated on 2022-05-25

42dee702a0bb71953071a07a1a27d7951d1b64d1/

NAME

IO::CatHandle::AutoLines - Get IO::CatHandle's current handle's line number

SYNOPSIS

use IO::CatHandle::AutoLines;

'some'   .IO.spurt: "a\nb\nc";
'files'  .IO.spurt: "d\ne\nf";
'to-read'.IO.spurt: "g\nh";

my $kitty = IO::CatHandle.new(<some files to-read>, :on-switch{
    say "Meow!"
}) does IO::CatHandle::AutoLines;

say "$kitty.ln(): $_" for $kitty.lines;

# OUTPUT:
# Meow!
# 1: a
# 2: b
# 3: c
# Meow!
# 1: d
# 2: e
# 3: f
# Meow!
# 1: g
# 2: h
# Meow!

DESCRIPTION

A role that adds an method to the IO::CatHandle type that will contain the current line number. Optionally, the lines counter can be reset when next source handle get switched into.

Note: only the .lines and .get methods are overriden to increment the line counter. Using any other methods to read data will not increment the line counter.

EXPORTED TYPES

role IO::CatHandle::AutoLines

Defined as:

role IO::CatHandle::AutoLines[Bool:D :$reset = True]

Provides an .ln method containing Int:D of the current line number. If :$reset parameter is set to True (default), then on source handle switch, the line number will be reset back to zero.

# Reset on-switch enabled
my $cat1 = IO::CatHandle.new(…) does role IO::CatHandle::AutoLines;

# Reset on-switch disabled
my $cat2 = IO::CatHandle.new(…) does role IO::CatHandle::AutoLines[:!reset];

AUTHOR

Zoffix Znet

COPYRIGHT AND LICENSE

This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.