bash - linux curly brackets instead of if-then-else-fi do-done -

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are curly brackets suitable replacement other constructs?

    [ -n "$test" ] && { xx='yes'; echo 'yes' } || { xx='no'; echo 'no' }

vs

    if [ -n "$test" ] ;        xx='yes'; echo 'yes'     else         xx='no'; echo 'no'     fi

another: 

    num in {000..2}; echo "$num"; done

or 

    num in {000..2}; { echo "$num"; }

in first example, a && b || c , if a; b else c have different behavior if b has non-zero exit status.

[ -n "$test" ] && { echo this; false; } || { echo "this too?"; }

your second example is should syntax error. nothing in documentation says can replace do/done pair compound command (which {...} is).

update: i'm told maintainer of bash undocumented feature provides backwards compatibility undocumented feature in original bourne shell.


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