local

TLDR

Declare local variable

$ local [varname]

Declare with initial value

$ local [varname]="[value]"

Declare integer variable

$ local -i [count]=0

Declare array

$ local -a [array]=([a] [b] [c])

Declare readonly local

$ local -r [constant]="[value]"

SYNOPSIS

local [option] name[=value] ...

local is a bash builtin that declares variables with local scope within a function. Local variables are not visible outside the function where they are declared.
Using local prevents function variables from polluting or conflicting with the global namespace.

PARAMETERS

-a

Declare as indexed array.

-A

Declare as associative array.

-i

Declare as integer.

-l

Convert to lowercase.

-u

Convert to uppercase.

-r

Make readonly.

-n

Name reference.

EXAMPLE

$ my_function() {
    local result="success"
    local -i count=5
    echo "$result: $count"
}
# $result and $count not accessible here

CAVEATS

Only valid inside functions. Not POSIX-compliant (use typeset for portability). Local variables shadow global ones. Subshells inherit but cannot modify.