Nested if else bash statement

Unlike boolean operators in other languages, && and || have the same precedence.

The tmpFlag=1 is treated as a statement and command and while it does not fail, there is nothing in bash that associates the || with the immediate previous term before a preceding &&, so the || is executed.

Here is a shorter snippet that makes that clear:

 tempFlag=1 ||echo nooooo && echo hello

Causes the echo hello to appear, because of echo noooo not because of the success of tempFlag=1.

Also consider this:

true && echo yes || echo no && echo yeeees || echo noooooo

give you both:

yes
yeeees

Explain please why it would not be better to write this with if ... elsif .. else ... fi instead? –

Also, why not use [ ]?

I would do it like this, much clearer:

if [ "$WRD" = "tmp" ] ; then
    tempFlag=1
elif [ "$someOtherVar" = "test" ] ; then
    tempFlag=2
else
    tempFlag=3
fi

PS, I also notice you have a typo, your first tmpFlag was supposed to be tempFlag. It doesn't change the behavior of course.

Another PS: using && and || instead of if .. elif .. fi is not really about the "[[ ]] functionality". You'd have the same problem if your were using the old test "[ ] functionality".

The test && command1 || command2 syntax does work as expected but if you append another command with &&, it breaks due to the operator precedence.
As a workaround, you can make compound commands as command2 by surrounding them with { ... }.
Then would you please try the following:

[[ $WRD == "tmp" ]] && tmpFlag=1 || { [[ $someOtherVar == "test" ]] && tmpFlag=2 || tmpFlag=3; }
echo "$tmpFlag"

• if I provide WRD as tmp, flag is set to 1.
• if I do not provide a WRD and $someOtherVar is test, then flag is set to 2.
• if I do not provide a WRD and $someOtherVar isn't test, then flag is set to 3.

I'm not sure if it is readable than if .. else .. syntax but it works.
Note that you have a typo in the variable name tmpFlag.

Hope this helps.

Just use braces for each of the "primary" options:

{ [[ $WRD == "tmp" ]] && tmpFlag=1 ; } || 
  { [[ $someOtherVar == "test" ]] && tempFlag=2; } || 
  tempFlag=3