nl_tokens: Copy the given symbol into symbol tables if the symbol has the given meaning and it doesn t already existed in the symbol table
pl_tokens: function copySymbol ( symbol , meaning ) { if ( symbol . flags & meaning ) { var id = symbol . name ; // We will copy all symbol regardless of its reserved name because // symbolsToArray will check whether the key is a reserved name and // it will not copy symbol with reserved name to the array if ( ! ts . hasProperty ( symbols , <mask> ) ) { symbols [ id ] = symbol ; } } }