Mathematica / Wolfram Language
I can think of several ways to do this in Mathematica; it'sMathematica is an interpreted language where important commandsin which command names are symbols that can be manipulated by the programmer. You can't delete built-in operators, but you can overload them or otherwise modify their function. The following scrambles the "With" command, which is needed for assignment to variables even internally, by preventing. This change prevents the kernel from holding arguments unevaluated until the assignment is complete. It, and it kills the language quite dead.
ClearAttributes["With", HoldAll]
This done at the start of aIf this command is run in an interactive session or at the top ofwithin a block of code and you can't, Mathematica will not even be able add 1+1
(the resulting error message is about a page long so I won't include it here).