# # the test/[ code is tested elsewhere, and the [[...]] just uses the same # code. this tests the special features of [[...]] # TDIR=/usr/homes/chet # this one is straight out of the ksh88 book [[ foo > bar && $PWD -ef . ]] echo returns: $? # [[ x ]] is equivalent to [[ -n x ]] [[ x ]] echo returns: $? # [[ ! x ]] is equivalent to [[ ! -n x ]] [[ ! x ]] echo returns: $? # ! binds tighter than test/[ -- it binds to a term, not an expression [[ ! x || x ]] echo returns: $? # parenthesized terms didn't work right until post-2.04 [[ a ]] echo returns: $? [[ (a) ]] echo returns: $? [[ -n a ]] echo returns: $? [[ (-n a) ]] echo returns: $? # unset variables don't need to be quoted [[ -n $UNSET ]] echo returns: $? [[ -z $UNSET ]] echo returns: $? # the ==/= and != operators do pattern matching [[ $TDIR == /usr/homes/* ]] echo returns: $? # ...but you can quote any part of the pattern to have it matched as a string [[ $TDIR == /usr/homes/\* ]] echo returns: $? [[ $TDIR == '/usr/homes/*' ]] echo returns: $? # if the first part of && fails, the second is not executed [[ -n $UNSET && $UNSET == foo ]] echo returns: $? [[ -z $UNSET && $UNSET == foo ]] echo returns: $? # if the first part of || succeeds, the second is not executed [[ -z $UNSET || -d $PWD ]] echo returns: $? # if the rhs were executed, it would be an error [[ -n $TDIR || $HOME -ef ${H*} ]] echo returns: $? [[ -n $TDIR && -z $UNSET || $HOME -ef ${H*} ]] echo returns: $? # && has a higher parsing precedence than || [[ -n $TDIR && -n $UNSET || $TDIR -ef . ]] echo returns: $? # ...but expressions in parentheses may be used to override precedence rules [[ -n $TDIR || -n $UNSET && $PWD -ef xyz ]] echo returns: $? [[ ( -n $TDIR || -n $UNSET ) && $PWD -ef xyz ]] echo returns: $? # some arithmetic tests for completeness -- see what happens with missing # operands, bad expressions, makes sure arguments are evaluated as # arithmetic expressions, etc. unset IVAR A [[ 7 -gt $IVAR ]] echo returns: $? [[ $IVAR -gt 7 ]] echo returns: $? IVAR=4 [[ $IVAR -gt 7 ]] echo returns: $? [[ 7 -eq 4+3 ]] echo returns: $? [[ 7 -eq 4+ ]] echo returns: $? IVAR=4+3 [[ $IVAR -eq 7 ]] echo returns: $? A=7 [[ $IVAR -eq A ]] echo returns: $? unset IVAR A # more pattern matching tests [[ $filename == *.c ]] echo returns: $? filename=patmatch.c [[ $filename == *.c ]] echo returns: $? # the extended globbing features may be used when matching patterns shopt -s extglob arg=-7 [[ $arg == -+([0-9]) ]] echo returns: $? arg=-H [[ $arg == -+([0-9]) ]] echo returns: $? arg=+4 [[ $arg == ++([0-9]) ]] echo returns: $? # make sure the null string is never matched if the string is not null STR=file.c PAT= if [[ $STR = $PAT ]]; then echo oops fi # but that if the string is null, a null pattern is matched correctly STR= PAT= if [[ $STR = $PAT ]]; then echo ok fi # test the regular expression conditional operator [[ jbig2dec-0.9-i586-001.tgz =~ ([^-]+)-([^-]+)-([^-]+)-0*([1-9][0-9]*)\.tgz ]] echo ${BASH_REMATCH[1]} # this shouldn't echo anything [[ jbig2dec-0.9-i586-001.tgz =~ \([^-]+\)-\([^-]+\)-\([^-]+\)-0*\([1-9][0-9]*\)\.tgz ]] echo ${BASH_REMATCH[1]} LDD_BASH=" linux-gate.so.1 => (0xffffe000) libreadline.so.5 => /lib/libreadline.so.5 (0xb7f91000) libhistory.so.5 => /lib/libhistory.so.5 (0xb7f8a000) libncurses.so.5 => /lib/libncurses.so.5 (0xb7f55000) libdl.so.2 => /lib/libdl.so.2 (0xb7f51000) libc.so.6 => /lib/libc.so.6 (0xb7e34000) /lib/ld-linux.so.2 (0xb7fd0000)" [[ "$LDD_BASH" =~ "libc" ]] && echo "found 1" echo ${BASH_REMATCH[@]} [[ "$LDD_BASH" =~ libc ]] && echo "found 2" echo ${BASH_REMATCH[@]} # bug in all versions up to and including bash-2.05b if [[ "123abc" == *?(a)bc ]]; then echo ok 42; else echo bad 42; fi if [[ "123abc" == *?(a)bc ]]; then echo ok 43; else echo bad 43; fi ${THIS_SH} ./cond-regexp.sub
