Local scope variables

-
# local makes variables local.
function thing { local l=8;echo $l;}
l=3
echo $l
3
thing
8
echo $l
3

...

# declare does exactly the same thing.
function thing { declare l=8;echo $l ;}
l=3
echo $l
3
thing
8
echo $l
3

...

# otherwise variables are global even inside functions.
function thing { l=8;echo $l ;}
l=3
echo $l
3
thing
8
echo $l
8

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