Hal9000
Variables leaking
I’ve been thinking about the change made 2-3 years ago where it’s
no longer permitted to set variables inside a case statement (or similar).
Is it fair to summarize this by saying: Variable values can pass from an
outer context to a more inner one, but those variables cannot be bound
to new values (such that the outer context changes)?
This afaik applies to any “block” of code nested inside a larger context –
the “guts” of an if, case, cond, code passed to a macro…
Am I looking at this correctly or not?
Hal
First Post!
hauleth
In short ways, binding is valid only within it’s block.
x = 1
if true do
# we start new block there
x = 2
# there `x` has new binding
end # block ended so all it's bindings as well
# there `x` has meaning of it's previous binding
Last Post!
Hal9000
Yes, thank you…
Of course, the value of x is still known inside the block until it is reassigned…
x = 1
IO.puts x
if true do
IO.puts x
x = 2
IO.puts x
end
IO.puts x
# Prints: 1, 1, 2, 1
Hal
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