Check try..catch exception variable name

[eharris]

I'm not sure this really matters enough to be worth it, so posing as a question. Do we want to try to keep try..catch exception variable names consistent?

In the current master head (excluding javascript), there are:

• 105 uses of x
• 87 uses of e
• 3 uses of ignored (I think this one should still be allowed)
• 2 uses of failed (I dislike this one a lot)
• 1 use of ex

The two top use cases are fairly even, so if we do want to do this, I'm fine with deciding on either one (I usually tend to use e myself)

The javascript seems to all use e or ex.

[jvoisin]

My vote goes to e, but it's really minor.

[muff1nman]

Doesn't bother me as long as we can keep ignored.