bash arrays, var substituions, etc

http://wiki.bash-hackers.org/syntax/pe
https://www.tldp.org/LDP/abs/html/parameter-substitution.html

The simplest way to copy a non-associative array in bash is to:
arrayClone=("${oldArray[@]}")


AAA=( $(git branch -a) )
AAA=( "${AAA[@]//remotes\/origin\/}" )

# split string on spaces, result is an array
p=( ${package_file//-/ } )


shopt -s extglob
A=aaaaXXaaa; echo "${A//+([^A-Z])/=}"
=XX=

A=aaaaXXaaa; echo "${A//+([A-Z])/=}"
aaaa=aaa

A=aaaa//aaa; echo "${A//+(\/)/=}"
aaaa=aaa

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CMD=( python3 somescript.py -r -d "$DAYS" )

if test -n "${EXTRA_PARAMS-}"; then
   IFS=" " read -r -a arr <<< "$EXTRA_PARAMS"
   CMD+=( "${arr[@]}" );
fi

# executing python script
"${CMD[@]}"
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