mirror of
https://gerrit.wikimedia.org/r/mediawiki/extensions/ParserFunctions
synced 2024-12-19 03:20:52 +00:00
637 lines
16 KiB
PHP
637 lines
16 KiB
PHP
<?php
|
||
|
||
if ( !defined( 'MEDIAWIKI' ) ) {
|
||
die( 'This file is a MediaWiki extension, it is not a valid entry point' );
|
||
}
|
||
|
||
// Character classes
|
||
define( 'EXPR_WHITE_CLASS', " \t\r\n" );
|
||
define( 'EXPR_NUMBER_CLASS', '0123456789.' );
|
||
|
||
// Token types
|
||
define( 'EXPR_WHITE', 1 );
|
||
define( 'EXPR_NUMBER', 2 );
|
||
define( 'EXPR_NEGATIVE', 3 );
|
||
define( 'EXPR_POSITIVE', 4 );
|
||
define( 'EXPR_PLUS', 5 );
|
||
define( 'EXPR_MINUS', 6 );
|
||
define( 'EXPR_TIMES', 7 );
|
||
define( 'EXPR_DIVIDE', 8 );
|
||
define( 'EXPR_MOD', 9 );
|
||
define( 'EXPR_OPEN', 10 );
|
||
define( 'EXPR_CLOSE', 11 );
|
||
define( 'EXPR_AND', 12 );
|
||
define( 'EXPR_OR', 13 );
|
||
define( 'EXPR_NOT', 14 );
|
||
define( 'EXPR_EQUALITY', 15 );
|
||
define( 'EXPR_LESS', 16 );
|
||
define( 'EXPR_GREATER', 17 );
|
||
define( 'EXPR_LESSEQ', 18 );
|
||
define( 'EXPR_GREATEREQ', 19 );
|
||
define( 'EXPR_NOTEQ', 20 );
|
||
define( 'EXPR_ROUND', 21 );
|
||
define( 'EXPR_EXPONENT', 22 );
|
||
define( 'EXPR_SINE', 23 );
|
||
define( 'EXPR_COSINE', 24 );
|
||
define( 'EXPR_TANGENS', 25 );
|
||
define( 'EXPR_ARCSINE', 26 );
|
||
define( 'EXPR_ARCCOS', 27 );
|
||
define( 'EXPR_ARCTAN', 28 );
|
||
define( 'EXPR_EXP', 29 );
|
||
define( 'EXPR_LN', 30 );
|
||
define( 'EXPR_ABS', 31 );
|
||
define( 'EXPR_FLOOR', 32 );
|
||
define( 'EXPR_TRUNC', 33 );
|
||
define( 'EXPR_CEIL', 34 );
|
||
define( 'EXPR_POW', 35 );
|
||
define( 'EXPR_PI', 36 );
|
||
|
||
class ExprError extends MWException {
|
||
public function __construct( $msg, $parameter = '' ) {
|
||
$this->message = '<strong class="error">' . wfMsgForContent( "pfunc_expr_$msg", htmlspecialchars( $parameter ) ) . '</strong>';
|
||
}
|
||
}
|
||
|
||
class ExprParser {
|
||
var $maxStackSize = 100;
|
||
|
||
var $precedence = array(
|
||
EXPR_NEGATIVE => 10,
|
||
EXPR_POSITIVE => 10,
|
||
EXPR_EXPONENT => 10,
|
||
EXPR_SINE => 9,
|
||
EXPR_COSINE => 9,
|
||
EXPR_TANGENS => 9,
|
||
EXPR_ARCSINE => 9,
|
||
EXPR_ARCCOS => 9,
|
||
EXPR_ARCTAN => 9,
|
||
EXPR_EXP => 9,
|
||
EXPR_LN => 9,
|
||
EXPR_ABS => 9,
|
||
EXPR_FLOOR => 9,
|
||
EXPR_TRUNC => 9,
|
||
EXPR_CEIL => 9,
|
||
EXPR_NOT => 9,
|
||
EXPR_POW => 8,
|
||
EXPR_TIMES => 7,
|
||
EXPR_DIVIDE => 7,
|
||
EXPR_MOD => 7,
|
||
EXPR_PLUS => 6,
|
||
EXPR_MINUS => 6,
|
||
EXPR_ROUND => 5,
|
||
EXPR_EQUALITY => 4,
|
||
EXPR_LESS => 4,
|
||
EXPR_GREATER => 4,
|
||
EXPR_LESSEQ => 4,
|
||
EXPR_GREATEREQ => 4,
|
||
EXPR_NOTEQ => 4,
|
||
EXPR_AND => 3,
|
||
EXPR_OR => 2,
|
||
EXPR_PI => 0,
|
||
EXPR_OPEN => -1,
|
||
EXPR_CLOSE => -1,
|
||
);
|
||
|
||
var $names = array(
|
||
EXPR_NEGATIVE => '-',
|
||
EXPR_POSITIVE => '+',
|
||
EXPR_NOT => 'not',
|
||
EXPR_TIMES => '*',
|
||
EXPR_DIVIDE => '/',
|
||
EXPR_MOD => 'mod',
|
||
EXPR_PLUS => '+',
|
||
EXPR_MINUS => '-',
|
||
EXPR_ROUND => 'round',
|
||
EXPR_EQUALITY => '=',
|
||
EXPR_LESS => '<',
|
||
EXPR_GREATER => '>',
|
||
EXPR_LESSEQ => '<=',
|
||
EXPR_GREATEREQ => '>=',
|
||
EXPR_NOTEQ => '<>',
|
||
EXPR_AND => 'and',
|
||
EXPR_OR => 'or',
|
||
EXPR_EXPONENT => 'e',
|
||
EXPR_SINE => 'sin',
|
||
EXPR_COSINE => 'cos',
|
||
EXPR_TANGENS => 'tan',
|
||
EXPR_ARCSINE => 'asin',
|
||
EXPR_ARCCOS => 'acos',
|
||
EXPR_ARCTAN => 'atan',
|
||
EXPR_LN => 'ln',
|
||
EXPR_EXP => 'exp',
|
||
EXPR_ABS => 'abs',
|
||
EXPR_FLOOR => 'floor',
|
||
EXPR_TRUNC => 'trunc',
|
||
EXPR_CEIL => 'ceil',
|
||
EXPR_POW => '^',
|
||
EXPR_PI => 'pi',
|
||
);
|
||
|
||
|
||
var $words = array(
|
||
'mod' => EXPR_MOD,
|
||
'and' => EXPR_AND,
|
||
'or' => EXPR_OR,
|
||
'not' => EXPR_NOT,
|
||
'round' => EXPR_ROUND,
|
||
'div' => EXPR_DIVIDE,
|
||
'e' => EXPR_EXPONENT,
|
||
'sin' => EXPR_SINE,
|
||
'cos' => EXPR_COSINE,
|
||
'tan' => EXPR_TANGENS,
|
||
'asin' => EXPR_ARCSINE,
|
||
'acos' => EXPR_ARCCOS,
|
||
'atan' => EXPR_ARCTAN,
|
||
'exp' => EXPR_EXP,
|
||
'ln' => EXPR_LN,
|
||
'abs' => EXPR_ABS,
|
||
'trunc' => EXPR_TRUNC,
|
||
'floor' => EXPR_FLOOR,
|
||
'ceil' => EXPR_CEIL,
|
||
'pi' => EXPR_PI,
|
||
);
|
||
|
||
/**
|
||
* Evaluate a mathematical expression
|
||
*
|
||
* The algorithm here is based on the infix to RPN algorithm given in
|
||
* http://montcs.bloomu.edu/~bobmon/Information/RPN/infix2rpn.shtml
|
||
* It's essentially the same as Dijkstra's shunting yard algorithm.
|
||
* @param $expr string
|
||
* @return string
|
||
*/
|
||
function doExpression( $expr ) {
|
||
$operands = array();
|
||
$operators = array();
|
||
|
||
# Unescape inequality operators
|
||
$expr = strtr( $expr, array( '<' => '<', '>' => '>',
|
||
'−' => '-', '−' => '-' ) );
|
||
|
||
$p = 0;
|
||
$end = strlen( $expr );
|
||
$expecting = 'expression';
|
||
|
||
while ( $p < $end ) {
|
||
if ( count( $operands ) > $this->maxStackSize || count( $operators ) > $this->maxStackSize ) {
|
||
throw new ExprError( 'stack_exhausted' );
|
||
}
|
||
$char = $expr[$p];
|
||
$char2 = substr( $expr, $p, 2 );
|
||
|
||
// Mega if-elseif-else construct
|
||
// Only binary operators fall through for processing at the bottom, the rest
|
||
// finish their processing and continue
|
||
|
||
// First the unlimited length classes
|
||
|
||
if ( false !== strpos( EXPR_WHITE_CLASS, $char ) ) {
|
||
// Whitespace
|
||
$p += strspn( $expr, EXPR_WHITE_CLASS, $p );
|
||
continue;
|
||
} elseif ( false !== strpos( EXPR_NUMBER_CLASS, $char ) ) {
|
||
// Number
|
||
if ( $expecting != 'expression' ) {
|
||
throw new ExprError( 'unexpected_number' );
|
||
}
|
||
|
||
// Find the rest of it
|
||
$length = strspn( $expr, EXPR_NUMBER_CLASS, $p );
|
||
// Convert it to float, silently removing double decimal points
|
||
$operands[] = floatval( substr( $expr, $p, $length ) );
|
||
$p += $length;
|
||
$expecting = 'operator';
|
||
continue;
|
||
} elseif ( ctype_alpha( $char ) ) {
|
||
// Word
|
||
// Find the rest of it
|
||
$remaining = substr( $expr, $p );
|
||
if ( !preg_match( '/^[A-Za-z]*/', $remaining, $matches ) ) {
|
||
// This should be unreachable
|
||
throw new ExprError( 'preg_match_failure' );
|
||
}
|
||
$word = strtolower( $matches[0] );
|
||
$p += strlen( $word );
|
||
|
||
// Interpret the word
|
||
if ( !isset( $this->words[$word] ) ) {
|
||
throw new ExprError( 'unrecognised_word', $word );
|
||
}
|
||
$op = $this->words[$word];
|
||
switch( $op ) {
|
||
// constant
|
||
case EXPR_EXPONENT:
|
||
if ( $expecting != 'expression' ) {
|
||
continue;
|
||
}
|
||
$operands[] = exp( 1 );
|
||
$expecting = 'operator';
|
||
continue 2;
|
||
case EXPR_PI:
|
||
if ( $expecting != 'expression' ) {
|
||
throw new ExprError( 'unexpected_number' );
|
||
}
|
||
$operands[] = pi();
|
||
$expecting = 'operator';
|
||
continue 2;
|
||
// Unary operator
|
||
case EXPR_NOT:
|
||
case EXPR_SINE:
|
||
case EXPR_COSINE:
|
||
case EXPR_TANGENS:
|
||
case EXPR_ARCSINE:
|
||
case EXPR_ARCCOS:
|
||
case EXPR_ARCTAN:
|
||
case EXPR_EXP:
|
||
case EXPR_LN:
|
||
case EXPR_ABS:
|
||
case EXPR_FLOOR:
|
||
case EXPR_TRUNC:
|
||
case EXPR_CEIL:
|
||
if ( $expecting != 'expression' ) {
|
||
throw new ExprError( 'unexpected_operator', $word );
|
||
}
|
||
$operators[] = $op;
|
||
continue 2;
|
||
}
|
||
// Binary operator, fall through
|
||
$name = $word;
|
||
}
|
||
|
||
// Next the two-character operators
|
||
|
||
elseif ( $char2 == '<=' ) {
|
||
$name = $char2;
|
||
$op = EXPR_LESSEQ;
|
||
$p += 2;
|
||
} elseif ( $char2 == '>=' ) {
|
||
$name = $char2;
|
||
$op = EXPR_GREATEREQ;
|
||
$p += 2;
|
||
} elseif ( $char2 == '<>' || $char2 == '!=' ) {
|
||
$name = $char2;
|
||
$op = EXPR_NOTEQ;
|
||
$p += 2;
|
||
}
|
||
|
||
// Finally the single-character operators
|
||
|
||
elseif ( $char == '+' ) {
|
||
++$p;
|
||
if ( $expecting == 'expression' ) {
|
||
// Unary plus
|
||
$operators[] = EXPR_POSITIVE;
|
||
continue;
|
||
} else {
|
||
// Binary plus
|
||
$op = EXPR_PLUS;
|
||
}
|
||
} elseif ( $char == '-' ) {
|
||
++$p;
|
||
if ( $expecting == 'expression' ) {
|
||
// Unary minus
|
||
$operators[] = EXPR_NEGATIVE;
|
||
continue;
|
||
} else {
|
||
// Binary minus
|
||
$op = EXPR_MINUS;
|
||
}
|
||
} elseif ( $char == '*' ) {
|
||
$name = $char;
|
||
$op = EXPR_TIMES;
|
||
++$p;
|
||
} elseif ( $char == '/' ) {
|
||
$name = $char;
|
||
$op = EXPR_DIVIDE;
|
||
++$p;
|
||
} elseif ( $char == '^' ) {
|
||
$name = $char;
|
||
$op = EXPR_POW;
|
||
++$p;
|
||
} elseif ( $char == '(' ) {
|
||
if ( $expecting == 'operator' ) {
|
||
throw new ExprError( 'unexpected_operator', '(' );
|
||
}
|
||
$operators[] = EXPR_OPEN;
|
||
++$p;
|
||
continue;
|
||
} elseif ( $char == ')' ) {
|
||
$lastOp = end( $operators );
|
||
while ( $lastOp && $lastOp != EXPR_OPEN ) {
|
||
$this->doOperation( $lastOp, $operands );
|
||
array_pop( $operators );
|
||
$lastOp = end( $operators );
|
||
}
|
||
if ( $lastOp ) {
|
||
array_pop( $operators );
|
||
} else {
|
||
throw new ExprError( 'unexpected_closing_bracket' );
|
||
}
|
||
$expecting = 'operator';
|
||
++$p;
|
||
continue;
|
||
} elseif ( $char == '=' ) {
|
||
$name = $char;
|
||
$op = EXPR_EQUALITY;
|
||
++$p;
|
||
} elseif ( $char == '<' ) {
|
||
$name = $char;
|
||
$op = EXPR_LESS;
|
||
++$p;
|
||
} elseif ( $char == '>' ) {
|
||
$name = $char;
|
||
$op = EXPR_GREATER;
|
||
++$p;
|
||
} else {
|
||
throw new ExprError( 'unrecognised_punctuation', UtfNormal::cleanUp( $char ) );
|
||
}
|
||
|
||
// Binary operator processing
|
||
if ( $expecting == 'expression' ) {
|
||
throw new ExprError( 'unexpected_operator', $name );
|
||
}
|
||
|
||
// Shunting yard magic
|
||
$lastOp = end( $operators );
|
||
while ( $lastOp && $this->precedence[$op] <= $this->precedence[$lastOp] ) {
|
||
$this->doOperation( $lastOp, $operands );
|
||
array_pop( $operators );
|
||
$lastOp = end( $operators );
|
||
}
|
||
$operators[] = $op;
|
||
$expecting = 'expression';
|
||
}
|
||
|
||
// Finish off the operator array
|
||
while ( $op = array_pop( $operators ) ) {
|
||
if ( $op == EXPR_OPEN ) {
|
||
throw new ExprError( 'unclosed_bracket' );
|
||
}
|
||
$this->doOperation( $op, $operands );
|
||
}
|
||
|
||
return implode( "<br />\n", $operands );
|
||
}
|
||
|
||
/**
|
||
* @param $op int
|
||
* @param $stack array
|
||
* @throws ExprError
|
||
*/
|
||
function doOperation( $op, &$stack ) {
|
||
switch ( $op ) {
|
||
case EXPR_NEGATIVE:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = -$arg;
|
||
break;
|
||
case EXPR_POSITIVE:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
break;
|
||
case EXPR_TIMES:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = $left * $right;
|
||
break;
|
||
case EXPR_DIVIDE:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
if ( $right == 0 ) {
|
||
throw new ExprError( 'division_by_zero', $this->names[$op] );
|
||
}
|
||
$stack[] = $left / $right;
|
||
break;
|
||
case EXPR_MOD:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
if ( $right == 0 ) {
|
||
throw new ExprError( 'division_by_zero', $this->names[$op] );
|
||
}
|
||
$stack[] = $left % $right;
|
||
break;
|
||
case EXPR_PLUS:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = $left + $right;
|
||
break;
|
||
case EXPR_MINUS:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = $left - $right;
|
||
break;
|
||
case EXPR_AND:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left && $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_OR:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left || $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_EQUALITY:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left == $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_NOT:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = ( !$arg ) ? 1 : 0;
|
||
break;
|
||
case EXPR_ROUND:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$digits = intval( array_pop( $stack ) );
|
||
$value = array_pop( $stack );
|
||
$stack[] = round( $value, $digits );
|
||
break;
|
||
case EXPR_LESS:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left < $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_GREATER:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left > $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_LESSEQ:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left <= $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_GREATEREQ:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left >= $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_NOTEQ:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = ( $left != $right ) ? 1 : 0;
|
||
break;
|
||
case EXPR_EXPONENT:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
$stack[] = $left * pow( 10, $right );
|
||
break;
|
||
case EXPR_SINE:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = sin( $arg );
|
||
break;
|
||
case EXPR_COSINE:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = cos( $arg );
|
||
break;
|
||
case EXPR_TANGENS:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = tan( $arg );
|
||
break;
|
||
case EXPR_ARCSINE:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
if ( $arg < -1 || $arg > 1 ) {
|
||
throw new ExprError( 'invalid_argument', $this->names[$op] );
|
||
}
|
||
$stack[] = asin( $arg );
|
||
break;
|
||
case EXPR_ARCCOS:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
if ( $arg < -1 || $arg > 1 ) {
|
||
throw new ExprError( 'invalid_argument', $this->names[$op] );
|
||
}
|
||
$stack[] = acos( $arg );
|
||
break;
|
||
case EXPR_ARCTAN:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = atan( $arg );
|
||
break;
|
||
case EXPR_EXP:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = exp( $arg );
|
||
break;
|
||
case EXPR_LN:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
if ( $arg <= 0 ) {
|
||
throw new ExprError( 'invalid_argument_ln', $this->names[$op] );
|
||
}
|
||
$stack[] = log( $arg );
|
||
break;
|
||
case EXPR_ABS:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = abs( $arg );
|
||
break;
|
||
case EXPR_FLOOR:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = floor( $arg );
|
||
break;
|
||
case EXPR_TRUNC:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = (int)$arg;
|
||
break;
|
||
case EXPR_CEIL:
|
||
if ( count( $stack ) < 1 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$arg = array_pop( $stack );
|
||
$stack[] = ceil( $arg );
|
||
break;
|
||
case EXPR_POW:
|
||
if ( count( $stack ) < 2 ) {
|
||
throw new ExprError( 'missing_operand', $this->names[$op] );
|
||
}
|
||
$right = array_pop( $stack );
|
||
$left = array_pop( $stack );
|
||
if ( false === ( $stack[] = pow( $left, $right ) ) ) {
|
||
throw new ExprError( 'division_by_zero', $this->names[$op] );
|
||
}
|
||
break;
|
||
default:
|
||
// Should be impossible to reach here.
|
||
throw new ExprError( 'unknown_error' );
|
||
}
|
||
}
|
||
}
|