);
}
-/* Produce a list of lexems from the given text. Possible lexems are:
+/* Produce a list of lexems (tokens) from the given text. Possible lexems are:
*
* LEX_LBRACE
* LEX_RBRACE
* LEX_TAG
* LEX_AUTOTAG
* LEX_PREDICATE
- * LEX_BOOLOP
+ * LEX_AND
+ * LEX_OR
* LEX_CONTEXT
* LEX_CLEAR
* LEX_INSERT
$ret[] = array ('type' => 'LEX_DEFINE', 'lineno' => $lineno);
break;
case 'and':
+ $ret[] = array ('type' => 'LEX_AND', 'lineno' => $lineno);
+ break;
case 'or':
- $ret[] = array ('type' => 'LEX_BOOLOP', 'load' => $buffer, 'lineno' => $lineno);
+ $ret[] = array ('type' => 'LEX_OR', 'lineno' => $lineno);
break;
case 'not':
$ret[] = array ('type' => 'LEX_NOT', 'lineno' => $lineno);
// LEX_PREDICATE
// LEX_TRUE
// LEX_FALSE
-// SYNT_NOTEXPR (1 argument, holding SYNT_EXPR)
-// SYNT_BOOLOP (2 arguments, each holding SYNT_EXPR)
+// SYNT_UNARY_EXPR (any of the above lexems in "load" or even SYNT_EXPR)
+// SYNT_NOT_EXPR (SYNT_UNARY_EXPR in "load")
+// SYNT_AND_EXPR (either one arg in "load" or two args in "left" and "right")
+// SYNT_EXPR (idem), in fact it's boolean OR, but we keep the naming for compatibility
// SYNT_DEFINITION (2 arguments: term and definition)
// SYNT_GRANT (2 arguments: decision and condition)
// SYNT_ADJUSTMENT (context modifier with action(s) and condition)
// on "shift" action to make EXPR parsing hungry one.
if
(
- $stacktop['type'] == 'SYNT_EXPR' and
- ($done < $todo) and
- $lexems[$done]['type'] == 'LEX_BOOLOP'
+ $stacktop['type'] == 'SYNT_AND_EXPR' and
+ ($done < $todo) and
+ $lexems[$done]['type'] == 'LEX_AND'
)
{
// shift!
}
array_push ($stack, $stacktop);
// First detect definition start to save the predicate from being reduced into
- // expression.
+ // unary expression.
+ // DEFINE ::= define PREDICATE
if
(
$stacktop['type'] == 'LEX_PREDICATE' and
);
continue;
}
+ // CTXMOD ::= clear
if
(
$stacktop['type'] == 'LEX_CLEAR'
);
continue;
}
+ // CTXMOD ::= insert TAG
if
(
$stacktop['type'] == 'LEX_TAG' and
);
continue;
}
+ // CTXMOD ::= remove TAG
if
(
$stacktop['type'] == 'LEX_TAG' and
);
continue;
}
+ // CTXMODLIST ::= CTXMOD
if
(
- $stacktop['type'] == 'SYNT_CTXMOD' and
- $stacksecondtop['type'] == 'SYNT_CTXMODLIST'
+ $stacktop['type'] == 'SYNT_CTXMOD'
)
{
- // reduce!
- array_pop ($stack);
array_pop ($stack);
array_push
(
(
'type' => 'SYNT_CTXMODLIST',
'lineno' => $stacktop['lineno'],
- 'load' => array_merge ($stacksecondtop['load'], array ($stacktop['load']))
+ 'load' => array ($stacktop['load'])
)
);
continue;
}
+ // CTXMODLIST ::= CTXMODLIST CTXMOD
if
(
- $stacktop['type'] == 'SYNT_CTXMOD'
+ $stacktop['type'] == 'SYNT_CTXMOD' and
+ $stacksecondtop['type'] == 'SYNT_CTXMODLIST'
)
{
- // reduce!
+ array_pop ($stack);
array_pop ($stack);
array_push
(
(
'type' => 'SYNT_CTXMODLIST',
'lineno' => $stacktop['lineno'],
- 'load' => array ($stacktop['load'])
+ 'load' => array_merge ($stacksecondtop['load'], array ($stacktop['load']))
)
);
continue;
// If a handle is found for reversing a production rule, do it and start a new
// cycle instead of advancing further on rule list. This will preserve rule priority
// in the grammar and keep us from an extra shift action.
+ // UNARY_EXPRESSION ::= true | false | TAG | AUTOTAG | PREDICATE
if
(
$stacktop['type'] == 'LEX_TAG' or // first look for tokens, which are most
$stack,
array
(
- 'type' => 'SYNT_EXPR',
+ 'type' => 'SYNT_UNARY_EXPR',
'lineno' => $stacktop['lineno'],
'load' => $stacktop
)
);
continue;
}
+ // UNARY_EXPRESSION ::= (EXPRESSION)
+ // Useful trick about AND- and OR-expressions is to check, if the
+ // node we are reducing contains only 1 argument. In this case
+ // discard the wrapper and join the "load" argument into new node directly.
if
(
- $stacktop['type'] == 'SYNT_EXPR' and
+ $stacktop['type'] == 'LEX_RBRACE' and
+ $stacksecondtop['type'] == 'SYNT_EXPR' and
+ $stackthirdtop['type'] == 'LEX_LBRACE'
+ )
+ {
+ // reduce!
+ array_pop ($stack);
+ array_pop ($stack);
+ array_pop ($stack);
+ array_push
+ (
+ $stack,
+ array
+ (
+ 'type' => 'SYNT_UNARY_EXPR',
+ 'lineno' => $stacksecondtop['lineno'],
+ 'load' => isset ($stacksecondtop['load']) ? $stacksecondtop['load'] : $stacksecondtop
+ )
+ );
+ continue;
+ }
+ // UNARY_EXPRESSION ::= not UNARY_EXPRESSION
+ if
+ (
+ $stacktop['type'] == 'SYNT_UNARY_EXPR' and
$stacksecondtop['type'] == 'LEX_NOT'
)
{
$stack,
array
(
- 'type' => 'SYNT_EXPR',
+ 'type' => 'SYNT_UNARY_EXPR',
'lineno' => $stacktop['lineno'],
'load' => array
(
- 'type' => 'SYNT_NOTEXPR',
+ 'type' => 'SYNT_NOT_EXPR',
'load' => $stacktop['load']
)
)
);
continue;
}
+ // AND_EXPRESSION ::= AND_EXPRESSION and UNARY_EXPRESSION
if
(
- $stacktop['type'] == 'LEX_RBRACE' and
- $stacksecondtop['type'] == 'SYNT_EXPR' and
- $stackthirdtop['type'] == 'LEX_LBRACE'
+ $stacktop['type'] == 'SYNT_UNARY_EXPR' and
+ $stacksecondtop['type'] == 'LEX_AND' and
+ $stackthirdtop['type'] == 'SYNT_AND_EXPR'
)
{
- // reduce!
array_pop ($stack);
array_pop ($stack);
array_pop ($stack);
- $stacksecondtop['lineno'] = $stacktop['lineno'];
array_push
(
$stack,
- $stacksecondtop
+ array
+ (
+ 'type' => 'SYNT_AND_EXPR',
+ 'lineno' => $stacktop['lineno'],
+ 'left' => isset ($stackthirdtop['load']) ? $stackthirdtop['load'] : $stackthirdtop,
+ 'right' => $stacktop['load']
+ )
);
continue;
}
+ // AND_EXPRESSION ::= UNARY_EXPRESSION
if
(
- $stacktop['type'] == 'SYNT_EXPR' and
- $stacksecondtop['type'] == 'LEX_BOOLOP' and
+ $stacktop['type'] == 'SYNT_UNARY_EXPR'
+ )
+ {
+ array_pop ($stack);
+ array_push
+ (
+ $stack,
+ array
+ (
+ 'type' => 'SYNT_AND_EXPR',
+ 'lineno' => $stacktop['lineno'],
+ 'load' => $stacktop['load']
+ )
+ );
+ continue;
+ }
+ // EXPRESSION ::= EXPRESSION or AND_EXPRESSION
+ if
+ (
+ $stacktop['type'] == 'SYNT_AND_EXPR' and
+ $stacksecondtop['type'] == 'LEX_OR' and
$stackthirdtop['type'] == 'SYNT_EXPR'
)
{
- // reduce!
array_pop ($stack);
array_pop ($stack);
array_pop ($stack);
(
'type' => 'SYNT_EXPR',
'lineno' => $stacktop['lineno'],
- 'load' => array
- (
- 'type' => 'SYNT_BOOLOP',
- 'subtype' => $stacksecondtop['load'],
- 'left' => $stackthirdtop['load'],
- 'right' => $stacktop['load']
- )
+ 'left' => isset ($stackthirdtop['load']) ? $stackthirdtop['load'] : $stackthirdtop,
+ 'right' => isset ($stacktop['load']) ? $stacktop['load'] : $stacktop
+ )
+ );
+ continue;
+ }
+ // EXPRESSION ::= AND_EXPRESSION
+ if
+ (
+ $stacktop['type'] == 'SYNT_AND_EXPR'
+ )
+ {
+ array_pop ($stack);
+ array_push
+ (
+ $stack,
+ array
+ (
+ 'type' => 'SYNT_EXPR',
+ 'lineno' => $stacktop['lineno'],
+ 'load' => isset ($stacktop['load']) ? $stacktop['load'] : $stacktop
)
);
continue;
}
+ // GRANT ::= DECISION EXPRESSION
if
(
$stacktop['type'] == 'SYNT_EXPR' and
);
continue;
}
+ // DEFINE ::= define PREDICATE
if
(
$stacktop['type'] == 'SYNT_EXPR' and
);
continue;
}
+ // ADJUSTMENT ::= context CTXMODLIST on EXPRESSION
if
(
$stacktop['type'] == 'SYNT_EXPR' and
);
continue;
}
+ // CODESENTENCE ::= DEFINITION | GRANT | ADJUSTMENT
+ // CODETEXT ::= CODESENTENCE | CODETEXT CODESENTENCE
if
(
($stacktop['type'] == 'SYNT_GRANT' or $stacktop['type'] == 'SYNT_DEFINITION' or $stacktop['type'] == 'SYNT_ADJUSTMENT') and
return TRUE;
case 'LEX_FALSE':
return FALSE;
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
$tmp = $self ($expr['load'], $tagchain, $ptable);
if ($tmp === TRUE)
return FALSE;
return TRUE;
else
return $tmp;
- case 'SYNT_BOOLOP':
- $leftresult = $self ($expr['left'], $tagchain, $ptable);
- switch ($expr['subtype'])
- {
- case 'or':
- if ($leftresult)
- return TRUE; // early success
- return $self ($expr['right'], $tagchain, $ptable);
- case 'and':
- if (!$leftresult)
- return FALSE; // early failure
- return $self ($expr['right'], $tagchain, $ptable);
- default:
- if (!$silent)
- showError ("Cannot evaluate unknown boolean operation '${boolop['subtype']}'");
- return NULL;
- }
+ case 'SYNT_AND_EXPR': // binary AND
+ if (FALSE == $self ($expr['left'], $tagchain, $ptable))
+ return FALSE; // early failure
+ return $self ($expr['right'], $tagchain, $ptable);
+ case 'SYNT_EXPR': // binary OR
+ if (TRUE == $self ($expr['left'], $tagchain, $ptable))
+ return TRUE; // early success
+ return $self ($expr['right'], $tagchain, $ptable);
default:
if (!$silent)
showError ("Evaluation error, cannot process expression type '${expr['type']}'", __FUNCTION__);
return NULL;
case 'LEX_PREDICATE':
return in_array ($expr['load'], $plist) ? NULL : $expr['load'];
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
return $self ($plist, $expr['load']);
case 'SYNT_BOOLOP':
if (($tmp = $self ($plist, $expr['left'])) !== NULL)
'text' => "Martian autotag '${expr['load']}'"
));
}
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
return $self ($expr['load']);
case 'SYNT_BOOLOP':
return array_merge
'class' => 'warning',
'text' => "Tag '${expr['load']}' does not exist."
));
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
return $self ($expr['load']);
case 'SYNT_BOOLOP':
return array_merge
return FALSE;
case 'LEX_PREDICATE':
return $pname == $expr['load'];
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
return $self ($pname, $expr['load']);
case 'SYNT_BOOLOP':
return $self ($pname, $expr['left']) or $self ($pname, $expr['right']);
case 'LEX_AUTOTAG':
case 'LEX_PREDICATE':
return 'sometimes something';
- case 'SYNT_NOTEXPR':
+ case 'SYNT_NOT_EXPR':
return $self ($expr['load']);
case 'SYNT_BOOLOP':
$leftanswer = $self ($expr['left']);
projects / racktables / commitdiff
