addCustomFunction() public method

Add a custom function to the parser. no return value
public addCustomFunction ( String $token ) : null
$token String The name of the function to add
return null
 public function testIssueGit183()
 {
     $query = "SELECT *\nFROM SC_CATALOG_DETAIL_REG CD\nINNER JOIN MASTER_ITEM_LOOKUP IL\nON to_number( CD.STYLE ) = to_number( IL.SKU_NUM )\n\t\t\t\t";
     $parser = new PHPSQLParser();
     $parser->addCustomFunction("to_number");
     $p = $parser->parse($query, true);
     $expected = getExpectedValue(dirname(__FILE__), 'issue_git183.serialized');
     $this->assertEquals($expected, $p, "Oracle\\'s to_number");
 }
 public function testCustomfunction()
 {
     try {
         $sql = "SELECT PERCENTILE(xyz, 90) as percentile from some_table";
         $parser = new PHPSQLParser();
         $parser->addCustomFunction("percentile");
         $p = $parser->parse($sql, true);
     } catch (\Exception $e) {
         $p = array();
     }
     $this->assertSame(ExpressionType::CUSTOM_FUNCTION, $p['SELECT'][0]['expr_type'], 'custom function within SELECT clause');
     $parser = new PHPSQLParser();
     $parser->addCustomFunction("percentile");
     $parser->addCustomFunction("foo_bar");
     $p = $parser->getCustomFunctions();
     $this->assertEquals(array("PERCENTILE", "FOO_BAR"), $p, 'custom function list');
     $parser = new PHPSQLParser();
     $parser->addCustomFunction("percentile");
     $parser->addCustomFunction("foo_bar");
     $parser->removeCustomFunction('percentile');
     $p = $parser->getCustomFunctions();
     $this->assertEquals(array("FOO_BAR"), $p, 'remove custom function from list');
 }