September 2013
Intermediate to advanced
548 pages
12h 25m
English
Content preview from Programming Erlang, 2nd Edition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Programming Style with Exceptions
Handling exceptions is not rocket science; the following sections contain some frequently occurring code patterns that we can reuse in our programs.
Improving Error Messages
One use of the error/1 BIF is to improve the quality of
error messages. If we call math:sqrt(X) with a
negative argument, we’ll see the
following:
| | 1> math:sqrt(-1). |
| | ** exception error: bad argument in an arithmetic expression |
| | in function math:sqrt/1 |
| | called as math:sqrt(-1) |
We can write a wrapper for this, which improves the error message.
| lib_misc.erl | |
| | sqrt(X) when X < 0 -> |
| | error({squareRootNegativeArgument, X}); |
| | sqrt(X) -> |
| | math:sqrt(X). |
| | 2> lib_misc:sqrt(-1). |
| | ** exception error: {squareRootNegativeArgument,-1} |
| | in function ... |
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.