[BUG] Constants in a loop fail

[Ph0enixKM]

Describe the bug
Declaring constant with declare -r or readonly commands seem to remove the ability to overshadow them with local variables. Meaning that once we create a constant variable A and then we reference it in some function that has some local variable inside with the same name A, then we still get an error, because name A is already globally reserved for that particular constant variable created initially.

foo() {
    declare -r A=12
}

declare -r A=12

foo # ERROR: A is already declared

The same error occurs for readonly.

To Reproduce

Here is a simple shell script that reproduces the error:

foo() {
    readonly test=12
}

# Declaring a constant will cause an error if it's being redeclared in the subsequent lines
readonly test=12

echo "FUNCTIONS"

foo
foo
foo

echo "LOOPS & FUNCTIONS"

for i in 0 1 2
do
    foo
done

echo "LOOPS"

for i in 0 1 2
do
    readonly test=12
done

Expected behavior
It should never error in the code above. Each constant is created for each iteration and then goes out of scope. The same fact applies to functions.

I think that the solution to this problem is to replace bash constants with regular variables and just check the constant usage in the compilation process.

[Ph0enixKM]

This issue should cover tests for declaring constants in cases of loops, functions, conditions.

[Mte90]

I think that the solution to this problem is to replace bash constants with regular variables and just check the constant usage in the compilation process.

That was my idea :-P Anyway the community voted at the time to do not do it in this way, but if there is no technical solution right now is the best option.