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# fixes for bugs in bash-4.2 regarding empty strings in expand_string_for_rhs
f=abc
recho ${f##""a}
recho ${f##"$v"a}
recho ${f%%""c}
recho ${f%%"$v"c}
recho ${f//""a}
recho ${f//"$v"a}
recho ${f/""a""b/}
recho ${f/""c/}
recho ${f/"$v"c/}
unset foo empty
foo=aabbcc
recho ${foo/bb/}
recho ${foo/bb/$empty}
recho ${foo/}
recho ${empty/}
recho ${foo/ }
recho ${empty/ }
unset foo empty
S2=oenophile
recho ${S2^"$v"[aeiou]}
recho ${S2^^"$v"[aeiou]}
recho ${foo:-""}
recho ${foo:-""abc}
recho "${foo:-''}"
recho "${foo:-}"
if [[ $var == "" ]]; then
echo good 1
fi
if [[ "$var"X == ""X ]]; then
echo good 2
fi
if [ "$var"X == ""X"" ]; then
echo good 3
fi
if [ X"" == X ]; then
echo good 4
fi
if [[ X"" == X ]]; then
echo good 5
fi
case x"" in
x) echo 'ok 1'
;;
x??) echo 'this would be really odd'
;;
x?) echo 'does this prove anything?'
echo x""x
;;
*) echo 'no match'
;;
esac
if [[ x"" == x ]]; then
echo ok 2
fi
if [[ x"" == x"" ]]; then
echo ok 3
else
echo bad 3
fi
case x"" in
x"") echo ok 4 ;;
*) echo bad 4;;
esac
if [[ x"" == x"" ]]; then
echo ok 5
else
echo bad 5
fi
case x"" in
"x") echo ok 6 ;;
*) echo bad 6;;
esac
case x"" in
"x") echo CTLNUL 7 ;;
x) echo ok 7 ;;
*) echo bad 7 ;;
esac
|