public function constraints($constraints, $context, array $options = []) {
		$defaults = ['prepend' => 'ON'];
		$options += $defaults;

		if (is_array($constraints)) {
			$constraints = $this->_constraints($constraints);
		}
		return $this->_conditions($constraints, $context, $options);
	}
public function constraints($constraints, $context, array $options = []) {
		$defaults = ['prepend' => 'ON'];
		$options += $defaults;

		if (is_array($constraints)) {
			$constraints = $this->_constraints($constraints);
		}
		return $this->_conditions($constraints, $context, $options);
	}
public function constraints ( $ constraints , $ context , array $ options = [ ] ) { $ defaults = [ 'prepend' => 'ON' ] ; $ options += $ defaults ; if ( is_array ( $ constraints ) ) { $ constraints = $ this -> _constraints ( $ constraints ) ; } return $ this -> _conditions ( $ constraints , $ context , $ options ) ; }
Returns a string of formatted constraints to be inserted into the query statement.

If the query constraints are defined as an array, key pairs are converted to SQL
strings. If `$key` is numeric and `$value` is a string, `$value` is treated as a literal
SQL fragment and returned.

@param string|array $constraints The constraints for a `ON` clause.
@param \lithium\data\model\Query $context
@param array $options Available options are:
- `'prepend'` _boolean|string_: The string to prepend or `false`
for no prepending. Defaults to `'ON'`.
@return string Returns the `ON` clause of an SQL query.
Returns a string of formatted constraints to be inserted into the query statement .