NAME
Ryu::Source - base representation for a source of events
SYNOPSIS
my $src = Ryu::Source->new;
my $chained = $src->map(sub { $_ * $_ })->prefix('value: ')->say;
$src->emit($_) for 1..5;
$src->finish;DESCRIPTION
This is probably the module you'd want to start with, if you were going to be using any of this. There's a disclaimer in Ryu that may be relevant at this point.
GLOBALS
$FUTURE_FACTORY
This is a coderef which should return a new Future-compatible instance.
Example overrides might include:
$Ryu::Source::FUTURE_FACTORY = sub { Mojo::Future->new->set_label($_[1]) };METHODS
new
Takes named parameters.
describe
Returns a string describing this source and any parents - typically this will result in a chain like from->combine_latest->count.
from
Creates a new source from things.
The precise details of what this method supports may be somewhat ill-defined at this point in time. It is expected that the interface and internals of this method will vary greatly in versions to come.
encode
Passes each item through an encoder.
The first parameter is the encoder to use, the remainder are used as options for the selected encoder.
Examples:
$src->encode('json')
$src->encode('utf8')
$src->encode('base64')decode
Passes each item through a decoder.
The first parameter is the decoder to use, the remainder are used as options for the selected decoder.
Examples:
$src->decode('json')
$src->decode('utf8')
$src->decode('base64')say
Shortcut for -each(sub { print "\n" }) >.
Shortcut for -each(sub { print }) >, except this will also save the initial state of $\ and use that for each call for consistency.
empty
Creates an empty source, which finishes immediately.
never
An empty source that never finishes.
throw
Throws something. I don't know what, maybe a chair.
METHODS - Instance
new_future
Used internally to get a Future.
pause
Does nothing useful.
resume
Is about as much use as "pause".
is_paused
Might return 1 or 0, but is generally meaningless.
debounce
Not yet implemented.
Requires timing support, see implementations such as Ryu::Async instead.
chomp
Chomps all items with the current delimiter.
Once you've instantiated this, it will stick with the delimiter which was in force at the time of instantiation. Said delimiter follows the usual rules of $/, whatever they happen to be.
map
A bit like "map" in perlfunc.
split
Splits the input into chunks. By default, will split into characters.
chunksize
Splits input into fixed-size chunks.
Note that output is always guaranteed to be a full chunk - if there is partial input at the time the input stream finishes, those extra bytes will be discarded.
as_list
Resolves to a list consisting of all items emitted by this source.
as_arrayref
Resolves to a single arrayref consisting of all items emitted by this source.
as_string
Concatenates all items into a single string.
Returns a Future which will resolve on completion.
combine_latest
with_index
Emits arrayrefs consisting of [ $item, $idx ].
with_latest_from
merge
apply
Used for setting up multiple streams.
Accepts a variable number of coderefs, will call each one and gather Ryu::Source results.
each_as_source
switch_str
Given a condition, will select one of the alternatives based on stringified result.
Example:
$src->switch_str(
sub { $_->name }, # our condition
smith => sub { $_->id }, # if this matches the condition, the code will be called with $_ set to the current item
jones => sub { $_->parent->id },
sub { undef } # and this is our default case
);ordered_futures
Given a stream of Futures, will emit the results as each Future is marked ready. If any fail, the stream will fail.
This is a terrible name for a method, expect it to change.
distinct
Emits new distinct items, using string equality with an exception for undef (i.e. undef is treated differently from empty string or 0).
Given 1,2,3,undef,2,3,undef,'2',2,4,1,5, you'd expect to get the sequence 1,2,3,undef,4,5.
distinct_until_changed
Removes contiguous duplicates, defined by string equality.
sort_by
Emits items sorted by the given key. This is a stable sort function.
The algorithm is taken from List::UtilsBy.
nsort_by
Emits items numerically sorted by the given key. This is a stable sort function.
See "sort_by".
rev_sort_by
Emits items sorted by the given key. This is a stable sort function.
The algorithm is taken from List::UtilsBy.
rev_nsort_by
Emits items numerically sorted by the given key. This is a stable sort function.
See "sort_by".
extract_all
Expects a regular expression and emits hashrefs containing the named capture buffers.
The regular expression will be applied using the m//gc operator.
Example:
$src->extract_all(qr{/(?<component>[^/]+)})
# emits { component => '...' }, { component => '...' }skip
Skips the first N items.
skip_last
Skips the last N items.
take
Takes a limited number of items.
Given a sequence of 1,2,3,4,5 and ->take(3), you'd get 1,2,3 and then the stream would finish.
first
Returns a source which provides the first item from the stream.
some
every
count
sum
mean
max
min
statistics
Emits a single hashref of statistics once the source completes.
filter
emit
flat_map
Similar to "map", but will flatten out some items:
an arrayref will be expanded out to emit the individual elements
for a Ryu::Source, passes on any emitted elements
This also means you can "merge" items from a series of sources.
Note that this is not recursive - an arrayref of arrayrefs will be expanded out into the child arrayrefs, but no further.
each
completed
METHODS - Proxied
The following methods are proxied to our completion Future:
then
is_ready
is_done
failure
is_cancelled
else
await
Block until this source finishes.
finish
Mark this source as completed.
METHODS - Internal
chained
Returns a new Ryu::Source chained from this one.
each_while_source
Like "each", but removes the source from the callback list once the parent completes.
AUTHOR
Tom Molesworth <TEAM@cpan.org>
LICENSE
Copyright Tom Molesworth 2011-2017. Licensed under the same terms as Perl itself.