DESCRIPTION
ESLIF is derived from perl's Marpa::R2, and has its own BNF, documented
in MarpaX::ESLIF::BNF.
The main features of this BNF are:
Sub-grammars
The number of sub grammars is unlimited.
Regular expressions
Native support of regular expression using the PCRE2
library (i.e. this is exactly perl
regexps, although very closed).
Streaming
Native support of streaming input.
Beginners might want to look at MarpaX::ESLIF::Introduction.
SYNOPSIS
use MarpaX::ESLIF;
my $eslif = MarpaX::ESLIF->new();
printf "ESLIF library version: %s\n", $eslif->version;
With a logger, using Log::Any::Adapter::Stderr as an example:
use MarpaX::ESLIF;
use Log::Any qw/$log/;
use Log::Any::Adapter ('Stderr', log_level => 'trace' );
my $eslif = MarpaX::ESLIF->new($log);
printf "ESLIF library version: %s\n", $eslif->version;
This class and its derivatives are thread-safe. Although there can be
many ESLIF instances, in practice a single instance is enough, unless
you want different logging interfaces. This is why the new method is
implemented as a multiton. Once a MarpaX::ESLIF instance is created,
the user should create a MarpaX::ESLIF::Grammar instance to have a
working grammar.
METHODS
MarpaX::ESLIF->new($loggerInterface)
my $loggerInterface = My::Logger::Interface->new();
my $eslif = MarpaX::ESLIF->new();
Returns an instance of MarpaX::ESLIF, noted $eslif below.
$loggerInterface is an optional parameter that, when its exists, must
be an object instance that can do the methods documented in
MarpaX::ESLIF::Logger::Interface, or undef.
An example of logging implementation can be a Log::Any adapter.
MarpaX::ESLIF->getInstance($loggerInterface)
Alias to new.
$eslif->version()
printf "ESLIF library version: %s\n", $eslif->version;
Returns a string containing the current underlying ESLIF library
version.
NOTES
The perl interface is an all-in-one version of marpaESLIF
library, which means that
character conversion is using iconv (or iconv-like on Windows) instead
of ICU, even if the later is available on your system.
BOOLEAN TYPE
ESLIF has a boolean type, perl has not. In order to not reinvent the
wheel, the widely JSON's Perl's boolean utilities via JSON::MaybeXS
wrapper are used, i.e.:
true
A true value. You may localize $MarpaX::ESLIF::true before using
ESLIF to change it.
Defaults to JSON::MaybeXS::true().
false
A false value. You may localize $MarpaX::ESLIF::false before using
ESLIF to change it.
Defaults to JSON::MaybeXS::false().
is_bool($value)
Returns a true value if $value is a boolean. You may localize
MarpaX::ESLIF::is_bool() function before using ESLIF to change it.
ESLIF always requires at least that $value is an object, object
nature then defaults to JSON::MaybeXS::is_bool($value)
INTEGER TYPE
ESLIF consider scalars that have only the internal IV flag.
FLOAT TYPE
ESLIF consider scalars that have only the internal NV flag.
STRING TYPE
ESLIF consider scalars that have only the internal PV flag.
SEE ALSO
MarpaX::ESLIF::Introduction, PCRE2 ,
MarpaX::ESLIF::BNF, MarpaX::ESLIF::Logger::Interface,
MarpaX::ESLIF::Grammar, MarpaX::ESLIF::Recognizer, Types::Standard,
JSON::MaybeXS.