RegisterStack
Contains TypoScript "Register" state together with class Register.
An instance of this class is created during frontend rendering and registered as Request attribute "frontend.register.stack".
The TypoScript "register" is a key-value store (implemented by class Register) combined with a stack. This has probably been invented for menu rendering back then: content objects in general and TypoScript based menu rendering specifically can be nested when multiple menu depths/layers are rendered. Each of those layers may need own values within their scope.
The two main usages are TypoScript data/getText to access register entries along with content objects LOAD_REGISTER and RESTORE_REGISTER which push and pop register objects from the stack and store key/value entries.
There is one quirk in comparison to a "classic" stack: New Register instances are typically clones of the underlying Register instance plus new key/values, see class LoadRegisterContentObject for an implementation: Values can be set on a lower level register and is still "seen/part of" a register on top. key/values bubble up, but not down.
This class is not part of the TYPO3 Core API
Table of Contents
Methods
- __construct() : mixed
- current() : Register
- Peek current Register. Does not change stack.
- pop() : Register
- Remove top of stack Register and return it.
- push() : void
- Add a new Register instance to top of stack
Methods
__construct()
public
__construct() : mixed
current()
Peek current Register. Does not change stack.
public
current() : Register
Return values
Registerpop()
Remove top of stack Register and return it.
public
pop() : Register
Re-inits with an empty register if empty to avoid exception or nullable handling in consumers if there is for example a "RESTORE_REGISTER" cObj too much. As drawback, consumers never know if there is a leftover pop().
Return values
Registerpush()
Add a new Register instance to top of stack
public
push(Register $register) : void
Parameters
- $register : Register