#ash# set +o posix #ash# declare -i iv jv echo "Format: 'expected actual'" iv=$(( 3 + 5 * 32 )) echo 163 $iv #ash# iv=iv+3 #ash# echo 166 $iv iv=2 jv=iv : $((jv *= 2)) ##hush## let "jv *= 2" echo 4 $jv jv=$(( $jv << 2 )) echo 16 $jv : $((jv=$jv / 2)) ##hush## let jv="$jv / 2" echo 8 $jv #ash# jv="jv >> 2" : $((jv=jv >> 2)) ##hush## let jv="jv >> 2" echo 2 $jv iv=$((iv+ $jv)) echo 4 $iv echo 2 $((iv -= jv)) echo 2 $iv echo 1 $(( iv == jv )) echo 0 $(( iv != $jv )) echo 0 $(( iv < jv )) echo 0 $(( $iv > $jv )) echo 1 $(( iv <= $jv )) echo 1 $(( $iv >= jv )) echo 2 $jv echo -3 $(( ~$jv )) echo -2 $(( ~1 )) echo 1 $(( ! 0 )) echo 0 $(( jv % 2 )) echo 2 $(( $iv % 4 )) echo 131072 $(( iv <<= 16 )) echo 29 $(( iv %= 33 )) echo 33 $(( 33 & 55 )) echo 49 $(( 33 | 17 )) echo 1 $(( iv && $jv )) echo 1 $(( $iv || jv )) echo 0 $(( iv && 0 )) echo 0 $(( iv & 0 )) echo 1 $(( iv && 1 )) echo 1 $(( iv & 1 )) echo 1 $(( $jv || 0 )) echo 2 $(( jv | 0 )) echo 3 $(( jv | 1 )) echo 1 $(( $jv || 1 )) : $((iv *= jv)) ##hush## let 'iv *= jv' echo 58 $iv echo 2 $jv : $((jv += $iv)) ##hush## let "jv += $iv" echo 60 $jv echo 1 $(( jv /= iv )) echo 256 $(( jv <<= 8 )) echo 16 $(( jv >>= 4 )) echo 62 $(( iv |= 4 )) echo 4 $(( iv &= 4 )) echo 29 $(( iv += (jv + 9))) echo 5 $(( (iv + 4) % 7 )) echo unary plus, minus echo -4 $(( +4 - 8 )) echo 4 $(( -4 + 8 )) echo conditional expressions echo 1 $(( 4<5 ? 1 : 32)) echo 32 $(( 4>5 ? 1 : 32)) echo 32 $(( 4>(2+3) ? 1 : 32)) echo 1 $(( 4<(2+3) ? 1 : 32)) echo 1 $(( (2+2)<(2+3) ? 1 : 32)) echo 32 $(( (2+2)>(2+3) ? 1 : 32)) echo 'check that parentheses in `cmd` are interpreted correctly' # \x28 is '(' echo 3 $(( ( `printf '(\x28 1'` + `echo 2\)\)` ) )) echo check that the unevaluated part of the ternary operator does not do evaluation or assignment x=i+=2 y=j+=2 #ash# declare -i i=1 j=1 i=1 j=1 echo 20 $((1 ? 20 : (x+=2))) #ash# echo $i,$x # ash mishandles this echo 30 $((0 ? (y+=2) : 30)) #ash# echo $j,$y # ash mishandles this x=i+=2 y=j+=2 #ash# declare -i i=1 j=1 i=1 j=1 echo 20 $((1 ? 20 : (x+=2))) #ash# echo $i,$x # ash mishandles this echo 30 $((0 ? (y+=2) : 30)) #ash# echo $i,$y # ash mishandles this echo check precedence of assignment vs. conditional operator # should be an error #ash# declare -i x=2 x=2 #ashnote# bash reports error but continues, ash aborts - using subshell to 'emulate' bash: ( y=$((1 ? 20 : x+=2)) ) echo check precedence of assignment vs. conditional operator #ash# declare -i x=2 x=2 # ash says "line NNN: syntax error: 0 ? x+=2 : 20" #ash# echo 20 $((0 ? x+=2 : 20)) echo associativity of assignment-operator operator #ash# declare -i i=1 j=2 k=3 i=1 j=2 k=3 echo 6 $((i += j += k)) echo 6,5,3 $i,$j,$k echo octal, hex echo 263 $(( 0x100 | 007 )) echo 255 $(( 0xff )) #ash# echo 255 $(( 16#ff )) #ash# echo 127 $(( 16#FF/2 )) #ash# echo 36 $(( 8#44 )) echo 40 $(( 8 ^ 32 )) #ash# # other bases #ash# echo 10 $(( 16#a )) #ash# echo 10 $(( 32#a )) #ash# echo 10 $(( 56#a )) #ash# echo 10 $(( 64#a )) #ash# #ash# echo 10 $(( 16#A )) #ash# echo 10 $(( 32#A )) #ash# echo 36 $(( 56#A )) #ash# echo 36 $(( 64#A )) #ash# #ash# echo 62 $(( 64#@ )) #ash# echo 63 $(( 64#_ )) #ash# # weird bases (error) #ash# echo $(( 3425#56 )) #ash# # missing number after base #ash# echo 0 $(( 2# )) # these should generate errors ( echo $(( 7 = 43 )) ) #ash# echo $(( 2#44 )) ( echo $(( 44 / 0 )) ) ( let 'jv += $iv' ) ( echo $(( jv += \$iv )) ) ( let 'rv = 7 + (43 * 6' ) #ash# # more errors #ash# declare -i i #ash# i=0#4 #ash# i=2#110#11 ((echo abc; echo def;); echo ghi) #ash# if (((4+4) + (4 + 7))); then #ash# echo ok #ash# fi #ash# (()) # make sure the null expression works OK #ash# a=(0 2 4 6) #ash# echo 6 $(( a[1] + a[2] )) #ash# echo 1 $(( (a[1] + a[2]) == a[3] )) #ash# (( (a[1] + a[2]) == a[3] )) ; echo 0 $? # test pushing and popping the expression stack unset A A="4 + " ( echo A $(( ( 4 + A ) + 4 )) ) A="3 + 5" echo 16 $(( ( 4 + A ) + 4 )) # badly-formed conditional expressions ( echo $(( 4 ? : $A )) ) ( echo $(( 1 ? 20 )) ) ( echo $(( 4 ? 20 : )) ) # precedence and short-circuit evaluation B=9 echo 9 $B # error ( echo $(( 0 && B=42 )); echo 9 $B ) # error ( echo $(( 1 || B=88 )); echo 9 $B ) # ash mistakenly evaluates B=... below #ash# echo 0 $(( 0 && (B=42) )) echo 9 $B #ash# echo 0 $(( (${$} - $$) && (B=42) )) echo 9 $B #ash# echo 1 $(( 1 || (B=88) )) echo 9 $B # until command with (( )) command x=7 echo 7 $x #ash# until (( x == 4 )) until test "$x" = 4 do echo $x x=4 done echo 4 $x # exponentiation echo 32767 $(( 2**15 - 1)) echo 32768 $(( 2**(16-1))) echo 131072 $(( 2**16*2 )) echo 2147483647 $(( 2**31-1)) echo 1 $(( 2**0 )) # {pre,post}-{inc,dec}rement and associated errors x=4 echo 4 $x echo 4 $(( x++ )) echo 5 $x echo 5 $(( x-- )) echo 4 $x echo 3 $(( --x )) echo 3 $x echo 4 $(( ++x )) echo 4 $x # ++ is not a inc operator on non-variable, it is the + + sequence echo 7 $(( ++7 )) ( echo $(( 7-- )) ) ( echo $(( --x=7 )) ) ( echo $(( ++x=7 )) ) ( echo $(( x++=7 )) ) ( echo $(( x--=7 )) ) echo 4 $x echo 7 $(( +7 )) echo -7 $(( -7 )) # ++ is not a inc operator on non-variable, it is the + + sequence echo $(( ++7 )) echo $(( --7 )) ${THIS_SH} ./arith1.sub ${THIS_SH} ./arith2.sub x=4 y=7 #ash# (( x=8 , y=12 )) x=8 y=12 echo $x $y #ash# # should be an error #ash# (( x=9 y=41 )) # These are errors unset b ( echo $((a b)) ) #ash# ((a b)) n=42 printf "%d\n" $n printf "%i\n" $n #ash# echo $(( 8#$(printf "%o\n" $n) )) printf "%u\n" $n #ash# echo $(( 16#$(printf "%x\n" $n) )) #ash# echo $(( 16#$(printf "%X\n" $n) )) # causes longjmp botches through bash-2.05b a[b[c]d]=e