protect
Protects a variable.
Syntax
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protect(X)-
Xis a variable
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protect(s)-
sis a string containing the name of a variable
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Description
If X is a variable (or a string containing the name of a variable), then protect(X) protects the variable. If successful, the function returns success.
When a variable is protected, its value cannot be changed and it cannot be deleted.
Examples
a ≔ 5
5
a ≔ 6
6
protect(a)
success
a ≔ 7
failure
Cannot modify or delete protected variable "a".
Call stack: assign
delete(a)
failure
Cannot modify or delete protected variable "a".
Call stack: delete
unprotect(a)
success
a ≔ 8
8
delete(a)
success