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Re: -e does not take effects in subshell

From: Linda Walsh
Subject: Re: -e does not take effects in subshell
Date: Thu, 20 Aug 2015 17:38:00 -0700
User-agent: Thunderbird

Chet Ramey wrote:
The earlier spec had -e only exit a script if a *simple* (external)
command failed.  It didn't include builtins nor functions.

This is not; builtins and functions are simple commands.
The builtins are _complex_ binary blobs that replace external commands.

Functions are a collection of many commands.  They are not a single,
simple statement.  I remember using their return value in some cases.

With the change, I couldn't run a func and have it return the
value in $? (1 byte, I know) -- but about 128x as flexible as "ok"/"die" (i.e. any non-zero value triggers the behavior
now, but before, it didn't).

My simplistic view was that -e was there to auto-exit if an external
command failed because they are "out of your control". But if I write a function -- I design the behavior. Even if I designed in
a bug -- it's still "my code" that has the problem not some
-_e_xternal command

----  cf. perl's option "autodie" -- you can say you want the "open
builtin" to just die on errors, then for simple scripts you don't have
to put extra code to handle each problem. I.e. -- it's not really something you want in production code, but I write far more throw away quick and dirty scripts than production ones.
I tried to write a more complex bash script one time -- that met my
expectations.  W/o error testing the code was about 150 lines.  With
error testing and _helpful_ error messages it was over 1000.
But that's the difference between quick&dirty vs. production.

-e was useful for Q&D, IMO....

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