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https://github.com/silverstripe/silverstripe-framework
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64 lines
1.2 KiB
PHP
64 lines
1.2 KiB
PHP
<?php
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require '../Parser.php' ;
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class Calculator extends Parser {
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/*!* Calculator
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Number: /[0-9]+/
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Value: Number > | '(' > Expr > ')' >
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function Number( &$result, $sub ) {
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$result['val'] = $sub['text'] ;
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}
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function Expr( &$result, $sub ) {
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$result['val'] = $sub['val'] ;
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}
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Times: '*' > operand:Value >
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Div: '/' > operand:Value >
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Product: Value > ( Times | Div ) *
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function Value( &$result, $sub ) {
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$result['val'] = $sub['val'] ;
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}
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function Times( &$result, $sub ) {
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$result['val'] *= $sub['operand']['val'] ;
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}
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function Div( &$result, $sub ) {
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$result['val'] /= $sub['operand']['val'] ;
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}
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Plus: '+' > operand:Product >
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Minus: '-' > operand:Product >
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Sum: Product > ( Plus | Minus ) *
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function Product( &$result, $sub ) {
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$result['val'] = $sub['val'] ;
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}
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function Plus( &$result, $sub ) {
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$result['val'] += $sub['operand']['val'] ;
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}
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function Minus( &$result, $sub ) {
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$result['val'] -= $sub['operand']['val'] ;
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}
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Expr: Sum
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function Sum( &$result, $sub ) {
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$result['val'] = $sub['val'] ;
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}
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*/
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}
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$x = new Calculator( '(2 + 4) * 3 - 10' ) ;
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$res = $x->match_Expr() ;
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if ( $res === FALSE ) {
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print "No Match\n" ;
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}
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else {
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print_r( $res ) ;
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}
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