File: test/test-recursion.js

var GrammarTemplate = require("../src/js/GrammarTemplate.js"), echo = console.log;

echo('GrammarTemplate.VERSION = ' + GrammarTemplate.VERSION);
echo( );

/*
    i.e: 
    foreach "expression:terms" as "term":
        foreach "term:factors" as "factor":
            ..
    
    here an :EXPR template is defined which itself uses (anonymous) sub-templates
    it is equivalent to (expand sub-templates to distinct):

<:FACTOR>:=[<lhs>[ <?op> <rhs|NULL>]]

<:TERM>:=[(<factor:FACTOR>[ AND <*factor:FACTOR>])]

<:EXPR>:=[<term:TERM>[ OR <*term:TERM>]]

<expression:EXPR>
<expression2:EXPR>

*/
var tpl = "<:EXPR>:=[<term>:=[(<factor>:=[<globalNegation:NEG><lhs>[ <?op:OP> <rhs|NULL>]][ AND <*factor>])][ OR <*term>]]<expression:EXPR>\n<expression2:EXPR>";

var expr = new GrammarTemplate( tpl );
GrammarTemplate.fnGlobal['NEG'] = function( val ) {
    return val ? 'NOT ' : '';
};
expr.fn['OP'] = function( val ) {
    return '!=' === val ? '<>' : val;
};
echo("input template:");
echo(tpl);

echo( );

echo("output:");
echo(expr.render({
    globalNegation: true,
    expression  : [
        // term
        [
            // factor
            {lhs: 1, op: '=', rhs: 1},
            // factor
            {lhs: 1, op: '=', rhs: 2},
            // factor
            {lhs: 1, op: '=', rhs: 3}
        ],
        // term
        [
            // factor
            {lhs: 1, op: '<', rhs: 1},
            // factor
            {lhs: 1, op: '<', rhs: 2},
            // factor
            {lhs: 1, op: '<', rhs: 3}
        ],
        // term
        [
            // factor
            {lhs: 1, op: '>', rhs: 1},
            // factor
            {lhs: 1, op: '>', rhs: 2},
            // factor
            {lhs: 1, op: '>', rhs: 3}
        ]
    ],
    expression2  : [
        // term
        [
            // factor
            {lhs: 2, op: '=', rhs: 1},
            // factor
            {lhs: 2, op: '=', rhs: 2},
            // factor
            {lhs: 2, op: '=', rhs: 3}
        ],
        // term
        [
            // factor
            {lhs: 2, op: '<', rhs: 1},
            // factor
            {lhs: 2, op: '<', rhs: 2},
            // factor
            {lhs: 2, op: '<', rhs: 3}
        ],
        // term
        [
            // factor
            {lhs: 2, op: '>', rhs: 1},
            // factor
            {lhs: 2, op: '>', rhs: 2},
            // factor
            {lhs: 2, op: '>', rhs: 3}
        ],
        // term
        [
            // factor
            {lhs: 3},
            // factor
            {lhs: 3, op: '!='}
        ]
    ]
}));