spunQ_PropertyParser Class Reference

Parser. More...

List of all members.

Public Member Functions

tokenize ($string)

Breaks a string down to its tokens.

parse ($string)

Parses a string to create a spunQ_IPLStatement.

parseComplexStatement ($string)

Parses a statement that could not be parsed by regular expressions.

Static Public Member Functions

static getInstance ()

Retrieves Singleton.

Public Attributes

const TOKEN_PARENTHESIS_OPEN = 1

Token: opening parenthesis '('.

const TOKEN_PARENTHESIS_CLOSE = 2

Token: closing parenthesis ')'.

const TOKEN_NOT = 4

Token: boolean negation '!'.

const TOKEN_EQUALS = 8

Token: equality operator '='.

const TOKEN_NOT_EQUALS = 12

Token: bitwise OR of not and equality operator '!='.

const TOKEN_LESS = 16

Token: operator less than '<'.

const TOKEN_LESS_EQUALS = 24

Token: bitwise OR of less than and equality operator '<='.

const TOKEN_GREATER = 32

Token: operator greater than '>'.

const TOKEN_GREATER_EQUALS = 40

Token: bitwise OR of greater than and equality operator '>='.

const TOKEN_BRACKET_OPEN = 64

Token: opening bracket '['.

const TOKEN_BRACKET_CLOSE = 128

Token: closing bracket ']'.

const TOKEN_ARRAY_ITEM_SEPARATOR = 256

Token: separator for array contents ','.

const TOKEN_PROPERTY = 512

Token: An object property.

const TOKEN_PROPERTY_SEPARATOR = 1024

Token: separator for chained properties '.

const TOKEN_OR = 2048

Token: boolean OR 'OR'.

const TOKEN_AND = 4096

Token: boolean AND 'AND'.

const TOKEN_CONSTANT = 8192

Token: constant string.

const TOKEN_LIKE = 16384

Token: 'like' operator.

const TOKEN_NOT_LIKE = 16388

Token: 'like' operator.

const TOKEN_WHITESPACE = 32768

Token: whitespace.

const TOKEN_COLON = 65536

Token: colon ':'.

const TOKEN_NULL = 131072

Token: null 'NULL'.

const TOKEN_IN = 262144

Token: in operator.

const TOKEN_NOT_IN = 262148

Token: in operator.

Protected Member Functions

__construct ()

Constructor.

getTokenUsingRegularExpression ($string, &$i, $regularExpression, $tokenConstant)

Extracts a token using a regular expression.

readConstantToken (&$string, &$i)

Reads a string token and advances the string index.

reduceParenthesisAndBrackets (&$tokens)

Replaces all balanced parenthesis and brackets with according objects.

parseOrStatement ($tokens, $from, $to)

Tries to parse an OR statement.

parseAndStatement ($tokens, $from, $to)

Tries to parse an AND statement.

parseComparison ($tokens, $from, $to)

Tries to parse a comparison.

parseValue ($tokens, $from, $to)

Tries to parse a value.

parsePropertyPath ($tokens, $from, $to)

Tries to parse a value.

parseConstantValue ($tokens, $from, $to)

Tries to parse a constant.

nextNonWhitespaceToken ($tokens, &$i, $to)

Advances a token index to the next non-whitespace token.

checkParsedToken ($tokens, $from, $to, $class)

Checks if a given class is already present in the $tokens array.

createStringAndPosition ($tokens, $offset, &$string, &$position)

Constructs a string and an index for the string from the $tokens array.

Protected Attributes

$oneCharacterTokens

Tokens that can easily be mapped to TOKEN_* constants.

Private Attributes

$parsedStrings = array()

Cache for strings that have been processed.

$cache

Static Private Attributes

static $instance

Singleton instance.

Detailed Description

Parser.

Language syntax:

   statement:
       or-chain
     | and-chain
     | comparison
     | value

   or-chain:
       statement 'OR' statement

   and-chain:
       statement 'AND' statement

   comparison:
       value operator value

   value:
       '!' value
     | property-path
     | constant-value
     | array '.' property-path
     | parenthesis-statement
     | parenthesis-statement '.' property-path

   property-path:
       property property-modifiers
     | property property-modifiers '.' property-path

   property-modifiers:
       <void>
     | property-modifier
     | property-modifier property-modifiers
   
   property-modifier:
       '[' statement ']'
     | '[=' statement ']'
     
   constant-value:
       '{' property '}'

   array:
       '[' array-contents ']'

   array-contents:
       value
     | value ',' array-contents

   parenthesis-statement:
       '(' statement ')'

   property:
       /[_a-z][_a-z0-9]* /

   operator:
       '<'
     | '>'
     | '='
     | '<='
     | '>='
     | '!='
     | 'IN'
     | '!IN'
     | 'LIKE'
     | '!LIKE'

Definition at line 73 of file PropertyParser.class.php.

Constructor & Destructor Documentation

spunQ_PropertyParser::__construct ( ) [protected]

Constructor.

Declared to reduce visibility.

Definition at line 242 of file PropertyParser.class.php.

Member Function Documentation

spunQ_PropertyParser::checkParsedToken	(	$	tokens,
		$	from,
		$	to,
		$	class
	)			`[protected]`

Checks if a given class is already present in the $tokens array.

Because we are processing some parts of the $tokens array in advance (namely parenthesis and brackets), it is well possible that the expected token is already present as an object in either of the parse* functions. This function checks that an object resides in the token within the range [$from-$to] (ignoring whitespace) and returns the object if it is present or NULL otherwise.

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	The object must be between the $from and $to indexes of the $tokens array.
	$to	see $token parameter.
	$class	The name of the class to look for.

Returns:: spunQ_IPLStatement Or NULL

Definition at line 736 of file PropertyParser.class.php.

spunQ_PropertyParser::createStringAndPosition	(	$	tokens,
		$	offset,
		&$	string,
		&$	position
	)			`[protected]`

Constructs a string and an index for the string from the $tokens array.

Needed to provide some useful feedback to the user. With this function we can display the character number that caused an error.

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$offset	The token number that had the error.
	$string	The string that will be generated (out-parameter).
	$position	The position within the string of the bogus token (out-parameter).

Returns:: void

Definition at line 770 of file PropertyParser.class.php.

static spunQ_PropertyParser::getInstance ( ) [static]

Retrieves Singleton.

Returns:: spunQ_PropertyParser

Definition at line 205 of file PropertyParser.class.php.

spunQ_PropertyParser::getTokenUsingRegularExpression	(	$	string,
		&$	i,
		$	regularExpression,
		$	tokenConstant
	)			`[protected]`

Extracts a token using a regular expression.

Parameters:

	$string	The string to extract from.
	$i	The index of the string the processing should start at. This parameter will point to the index after the extracted string.
	$regularExpression	The regular expression to use. Should not contain leading/trailing delimiters. Will be run with the modifiers i (case-insensitive) and s (match newlines).
	$tokenConstant	The TOKEN_* constant for this token.

Returns:: array<any> A token array. Fulfills the specification of the inner array of the return type of tokenize().

Definition at line 358 of file PropertyParser.class.php.

spunQ_PropertyParser::nextNonWhitespaceToken	(	$	tokens,
		&$	i,
		$	to
	)			`[protected]`

Advances a token index to the next non-whitespace token.

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$i	The index to advance.
	$to	The maximum value $i can have.

Returns:: array<any> The next token array.

Definition at line 709 of file PropertyParser.class.php.

spunQ_PropertyParser::parse ( $ string )

Parses a string to create a spunQ_IPLStatement.

Tries to parse using regular expressions and passes the string to parseComplexStatement() if it does not work.

Parameters:

$string

the property path string

Returns:: spunQ_IPLStatement

Definition at line 296 of file PropertyParser.class.php.

spunQ_PropertyParser::parseAndStatement	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse an AND statement.

Next in chain: comparison

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Definition at line 509 of file PropertyParser.class.php.

spunQ_PropertyParser::parseComparison	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse a comparison.

Next in chain: value

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Todo:

Continue here: several comparisons don't make any sense, check them. Some examples:

(a AND b) > 4 (less/greater with boolean)
1 != 2 > 4 (less/greater with boolean)
a < NULL (less/greater with NULL)

Definition at line 551 of file PropertyParser.class.php.

spunQ_PropertyParser::parseComplexStatement ( $ string )

Parses a statement that could not be parsed by regular expressions.

The parsing is done with the following steps:

The string is tokenized using tokenize().
The tokens are passed to reduceParenthesisAndBrackets() to process any balanced parenthesis and brackets that are detected. The resulting $tokens array contains parsed spunQ_IPLStatement object.
The $tokens are passed to parseOrStatement(), which checks if there is an OR statement at all. If not, it passes the $tokens to parseAndStatement() to see if that can parse an AND expression, and so on until parseConstantValue() or parsePropertyPath() are reached. So parseOrStatement(), for example, is not guaranteed to return an OR statement!

Parameters:

$string

the statement to parse.

Returns:: spunQ_IPLStatement

Definition at line 401 of file PropertyParser.class.php.

spunQ_PropertyParser::parseConstantValue	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse a constant.

Next in chain: <nothing>

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Definition at line 682 of file PropertyParser.class.php.

spunQ_PropertyParser::parseOrStatement	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse an OR statement.

Next in chain: AND statement

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Definition at line 473 of file PropertyParser.class.php.

spunQ_PropertyParser::parsePropertyPath	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse a value.

Next in chain: propertypath or constant

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Definition at line 624 of file PropertyParser.class.php.

spunQ_PropertyParser::parseValue	(	$	tokens,
		$	from,
		$	to
	)			`[protected]`

Tries to parse a value.

Next in chain: propertypath or constant

See also:: parseComplexStatement()

Parameters:

	$tokens	array containing the tokens (and possibly some objects).
	$from	Start processing at this index of the tokens array (inclusive).
	$to	process up to this index (inclusive).

Returns:: spunQ_IPLStatement

Definition at line 599 of file PropertyParser.class.php.

spunQ_PropertyParser::readConstantToken	(	&$	string,
		&$	i
	)			`[protected]`

Reads a string token and advances the string index.

Parameters:

	$string	The string to read from
	$i	the index to start extracting the string from. This parameter will point at the position after the string when the operation finishes.

Returns:: array<any> A token array. Fulfills the specification of the inner array of the return type of tokenize().

Exceptions:

spunQ_PropertyPathException

Definition at line 374 of file PropertyParser.class.php.

spunQ_PropertyParser::reduceParenthesisAndBrackets ( &$ tokens ) [protected]

Replaces all balanced parenthesis and brackets with according objects.

Parenthesis will be replaced by the spunQ_IPLStatement they evaluate to and brackets by either spunQ_PLArrayTransformation or spunQ_PLArrayReduction.

See also:: parseComplexStatement()

Parameters:

$tokens

array<array<any>> as returned by tokenize().

Returns:: array<any> Some tokens might be replaced by spunQ_IPLStatement objects.

Definition at line 417 of file PropertyParser.class.php.

spunQ_PropertyParser::tokenize ( $ string )

Breaks a string down to its tokens.

Parameters:

$string

The string to process

Returns:: array<array<any>> The inner array contains the TOKEN_* constant as the first entry and the string representation as the second.

Exceptions:

spunQ_PropertyPathException

Definition at line 260 of file PropertyParser.class.php.

Member Data Documentation

spunQ_PropertyParser::$instance [static, private]

Singleton instance.

Type:: spunQ_PropertyParser

Definition at line 199 of file PropertyParser.class.php.

spunQ_PropertyParser::$oneCharacterTokens [protected]

Initial value:

 array(
        '(' => self::TOKEN_PARENTHESIS_OPEN,
        ')' => self::TOKEN_PARENTHESIS_CLOSE,
        '[' => self::TOKEN_BRACKET_OPEN,
        ']' => self::TOKEN_BRACKET_CLOSE,
        '<' => self::TOKEN_LESS,
        '>' => self::TOKEN_GREATER,
        '!' => self::TOKEN_NOT,
        '=' => self::TOKEN_EQUALS,
        ':' => self::TOKEN_COLON,
        '.' => self::TOKEN_PROPERTY_SEPARATOR,
        ',' => self::TOKEN_ARRAY_ITEM_SEPARATOR,
    )

Tokens that can easily be mapped to TOKEN_* constants.

Type:: map<string,integer> As associative array.

Definition at line 216 of file PropertyParser.class.php.

spunQ_PropertyParser::$parsedStrings = array() [private]

Cache for strings that have been processed.

Type:: map<string,spunQ_IPLStatement> As associative array.

Definition at line 234 of file PropertyParser.class.php.

const spunQ_PropertyParser::TOKEN_PROPERTY_SEPARATOR = 1024

Token: separator for chained properties '.

'

Definition at line 143 of file PropertyParser.class.php.

The documentation for this class was generated from the following file:

PropertyParser.class.php


Public Member Functions
	tokenize ($string)
	Breaks a string down to its tokens.
	parse ($string)
	Parses a string to create a spunQ_IPLStatement.
	parseComplexStatement ($string)
	Parses a statement that could not be parsed by regular expressions.
Static Public Member Functions
static	getInstance ()
	Retrieves Singleton.
Public Attributes
const	TOKEN_PARENTHESIS_OPEN = 1
	Token: opening parenthesis '('.
const	TOKEN_PARENTHESIS_CLOSE = 2
	Token: closing parenthesis ')'.
const	TOKEN_NOT = 4
	Token: boolean negation '!'.
const	TOKEN_EQUALS = 8
	Token: equality operator '='.
const	TOKEN_NOT_EQUALS = 12
	Token: bitwise OR of not and equality operator '!='.
const	TOKEN_LESS = 16
	Token: operator less than '<'.
const	TOKEN_LESS_EQUALS = 24
	Token: bitwise OR of less than and equality operator '<='.
const	TOKEN_GREATER = 32
	Token: operator greater than '>'.
const	TOKEN_GREATER_EQUALS = 40
	Token: bitwise OR of greater than and equality operator '>='.
const	TOKEN_BRACKET_OPEN = 64
	Token: opening bracket '['.
const	TOKEN_BRACKET_CLOSE = 128
	Token: closing bracket ']'.
const	TOKEN_ARRAY_ITEM_SEPARATOR = 256
	Token: separator for array contents ','.
const	TOKEN_PROPERTY = 512
	Token: An object property.
const	TOKEN_PROPERTY_SEPARATOR = 1024
	Token: separator for chained properties '.
const	TOKEN_OR = 2048
	Token: boolean OR 'OR'.
const	TOKEN_AND = 4096
	Token: boolean AND 'AND'.
const	TOKEN_CONSTANT = 8192
	Token: constant string.
const	TOKEN_LIKE = 16384
	Token: 'like' operator.
const	TOKEN_NOT_LIKE = 16388
	Token: 'like' operator.
const	TOKEN_WHITESPACE = 32768
	Token: whitespace.
const	TOKEN_COLON = 65536
	Token: colon ':'.
const	TOKEN_NULL = 131072
	Token: null 'NULL'.
const	TOKEN_IN = 262144
	Token: in operator.
const	TOKEN_NOT_IN = 262148
	Token: in operator.
Protected Member Functions
	__construct ()
	Constructor.
	getTokenUsingRegularExpression ($string, &$i, $regularExpression, $tokenConstant)
	Extracts a token using a regular expression.
	readConstantToken (&$string, &$i)
	Reads a string token and advances the string index.
	reduceParenthesisAndBrackets (&$tokens)
	Replaces all balanced parenthesis and brackets with according objects.
	parseOrStatement ($tokens, $from, $to)
	Tries to parse an OR statement.
	parseAndStatement ($tokens, $from, $to)
	Tries to parse an AND statement.
	parseComparison ($tokens, $from, $to)
	Tries to parse a comparison.
	parseValue ($tokens, $from, $to)
	Tries to parse a value.
	parsePropertyPath ($tokens, $from, $to)
	Tries to parse a value.
	parseConstantValue ($tokens, $from, $to)
	Tries to parse a constant.
	nextNonWhitespaceToken ($tokens, &$i, $to)
	Advances a token index to the next non-whitespace token.
	checkParsedToken ($tokens, $from, $to, $class)
	Checks if a given class is already present in the $tokens array.
	createStringAndPosition ($tokens, $offset, &$string, &$position)
	Constructs a string and an index for the string from the $tokens array.
Protected Attributes
	$oneCharacterTokens
	Tokens that can easily be mapped to TOKEN_* constants.
Private Attributes
	$parsedStrings = array()
	Cache for strings that have been processed.
	$cache
Static Private Attributes
static	$instance
	Singleton instance.