summaryrefslogtreecommitdiff
path: root/extensions/ParserFunctions/Expr.php
diff options
context:
space:
mode:
Diffstat (limited to 'extensions/ParserFunctions/Expr.php')
-rw-r--r--extensions/ParserFunctions/Expr.php555
1 files changed, 555 insertions, 0 deletions
diff --git a/extensions/ParserFunctions/Expr.php b/extensions/ParserFunctions/Expr.php
new file mode 100644
index 00000000..299d382d
--- /dev/null
+++ b/extensions/ParserFunctions/Expr.php
@@ -0,0 +1,555 @@
+<?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.
+ */
+ function doExpression( $expr ) {
+ $operands = array();
+ $operators = array();
+
+ # Unescape inequality operators
+ $expr = strtr( $expr, array( '&lt;' => '<', '&gt;' => '>',
+ '&minus;' => '-', '−' => '-' ) );
+
+ $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 );
+ }
+
+ 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' );
+ }
+ }
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-12-20 17:18:54 +0000