page

Class: Lst

page.EBNFP. Lst

Represents a delimited iteration for EBNFP.

<private> new Lst(_node, _delim, _min)

Creates a new representation of a delimited iteration for EBNFP.

Parameters:
Name Type Description
_node epNode

body.
_delim epNode

delimiter.
_min number

minimum number of occurences, 0 or 1.
Properties:
Name Type Description
node epNode

body.
delim epNode

delimiter.
min number

minimum number of occurences, 0 or 1.
nt page.BNF.NT

corresponding non-terminal for BNF.
empty boolean

true if no input can be accepted.
first Map

terminals at front, maps ord to page.BNF.T.
follow Map

terminals following, maps ord to page.BNF.T.
Source:
Example
some: item +/ delimiter;
many: item ⭑/ delimiter;

Extends

Methods

<private> init()

Called once by page.EBNF#init to complete EBNF grammar initialization. Imports page.BNF.NT.empty, page.BNF.NT.first, and page.BNF.NT.follow from page.EBNF.Lst#nt and then delegates to the descendants.

Inherited From:
Source:

<private> toBNF(_grammar [, _nt])

Called once by page.EBNF#init to recursively translate into BNF.

a +/ b
a ⭑/ b

where .min is 1 or 0, respectively, are translated to

$#:  ;         # for min == 0
$#:  a $##;    # factored out
$##: ;
$##: b a $##;
Parameters:
Name Type Argument Description
_grammar page.EBNF

object to which the construct belongs.
_nt page.EBNF.NT <optional>

left-hand side, if known; avoids the need for a fresh non-terminal.
Inherited From:
Source:
Returns:

non-terminal representing the translated construct.

Type
page.BNF.NT

<private> toBNF(_grammar [, _nt])

Called once by page.EBNFP#init to recursively translate into BNF.

a +/ b
a ⭑/ b

where .min is 1 or 0, respectively, are translated to

$#:  %prec error;         # for min == 0
$#:  a $## %prec error;   # factored out
$#:  error $##;
$##: %prec error;
$##: $## b a;
$##: $# error a;
$##: $# b error;
$##: $# error;

error depends on _grammar.recover and %prec error is inserted if the grammar specifies %right error.

Parameters:
Name Type Argument Description
_grammar page.EBNFP

object to which the construct belongs.
_nt page.EBNF.NT <optional>

left-hand side, if known; avoids the need for a fresh non-terminal.
Source:
Returns:

non-terminal representing the translated construct.

Type
page.BNF.NT

toString()

Displays delimited iteration in EBNF notation.

Inherited From:
Source:
Returns:
Type
string