Sometimes other people can easily find what’s not right with us, even before we realize it. It is true with other people’s code too. If something goes wrong in our code, sometimes it is a library routine that catches it first. In normal case, it is easy to fall into the "it can't happen" mentality.
But pragmatic programmers always code defensively. We always look for rogue pointers in other parts of the program. We always check that the correct versions of shared libraries were actually loaded.
All errors give you information. You could convince yourself that the error can't happen, and choose to ignore it. Instead, Pragmatic Programmers tell themselves that if there is an error, something very, very bad has happened.
Crash, Don’t Trash
It is always better to crash immediately after finding a problem than going wrong indefinitely. One example for this is Java. It throws an exception when something wrong happens. If that exception is not handled properly, the execution stops. In languages like C, which doesn’t not support exceptions, we can make use of macros.
When our code discovers that something that was supposed to be impossible happened, our program is no longer viable. Terminate it as soon as possible. A dead program normally does a lot less damage than a crippled one.
- summary of Dead Programs Tell No Lies, from The Pragmatic Programmer: from Journeyman to Master
But pragmatic programmers always code defensively. We always look for rogue pointers in other parts of the program. We always check that the correct versions of shared libraries were actually loaded.
All errors give you information. You could convince yourself that the error can't happen, and choose to ignore it. Instead, Pragmatic Programmers tell themselves that if there is an error, something very, very bad has happened.
Crash, Don’t Trash
It is always better to crash immediately after finding a problem than going wrong indefinitely. One example for this is Java. It throws an exception when something wrong happens. If that exception is not handled properly, the execution stops. In languages like C, which doesn’t not support exceptions, we can make use of macros.
When our code discovers that something that was supposed to be impossible happened, our program is no longer viable. Terminate it as soon as possible. A dead program normally does a lot less damage than a crippled one.
- summary of Dead Programs Tell No Lies, from The Pragmatic Programmer: from Journeyman to Master
No comments:
Post a Comment