Req #69738 [Opn]: Declare immutable variables

Edit report at https://bugs.php.net/bug.php?id=69738&edit=1 ID: 69738 Updated by: chx@php.net Reported by: ugoren at interwise dot co dot il Summary: Declare immutable variables Status: Open Type: Feature/Change Request -Package: PHP Language Specification +Package: Variables related PHP Version: Irrelevant Block user comment: N Private report: N New Comment: The language specification describes the language as it is. This is a feature request against the language itself. Previous Comments: ------------------------------------------------------------------------ [2015-06-01 11:06:02] ugoren at interwise dot co dot il Description: ------------ I would like to have an option to declare immutable variables, for example $a=1;// is a mutable variable #b=1;// is an immutable variable The advantages of immutable variables are numerous: 1. caching function return values 2. parallelism (no shared memory) 3. pass variables by reference 4. Testability, just record a pure function's input and outputs, and you have automatically generated unit-tests. Test script: --------------- //sample code: #a=array(1,2); #a=array(1,3);//ok #a[1]=4;//error: modifying immutable variable //pure functions: function #pure_function(#a,#b) { return #a+#b; } ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=69738&edit=1