NAME

MarpaX::ESLIF - ESLIF is Extended ScanLess InterFace

VERSION

version 3.0.18

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.

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 <not> exactly perl regexps, although very closed).

Streaming

Native support of streaming input.

Beginners might want to look at MarpaX::ESLIF::Introduction.

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.

AUTHOR

Jean-Damien Durand <jeandamiendurand@free.fr>

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Jean-Damien Durand.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.