annotate src/except.h @ 1:cf0892e34f45

Resyncing with Git repo
author Eric Wing <ewing . public |-at-| gmail . com>
date Wed, 27 Aug 2008 22:44:22 -0700
parents 4b915342e2a8
children
rev   line source
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4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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1 #ifndef EXCEPT_H
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2 #define EXCEPT_H
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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3 /*=========================================================================*\
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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4 * Exception control
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5 * LuaSocket toolkit (but completely independent from other modules)
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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6 *
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7 * This provides support for simple exceptions in Lua. During the
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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8 * development of the HTTP/FTP/SMTP support, it became aparent that
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9 * error checking was taking a substantial amount of the coding. These
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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10 * function greatly simplify the task of checking errors.
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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11 *
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12 * The main idea is that functions should return nil as its first return
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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13 * value when it finds an error, and return an error message (or value)
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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14 * following nil. In case of success, as long as the first value is not nil,
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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15 * the other values don't matter.
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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16 *
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17 * The idea is to nest function calls with the "try" function. This function
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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18 * checks the first value, and calls "error" on the second if the first is
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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19 * nil. Otherwise, it returns all values it received.
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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20 *
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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21 * The protect function returns a new function that behaves exactly like the
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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22 * function it receives, but the new function doesn't throw exceptions: it
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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23 * returns nil followed by the error message instead.
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24 *
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25 * With these two function, it's easy to write functions that throw
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26 * exceptions on error, but that don't interrupt the user script.
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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27 *
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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28 * RCS ID: $Id: except.h,v 1.2 2005/09/29 06:11:41 diego Exp $
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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29 \*=========================================================================*/
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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30
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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31 #include "lua.h"
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32
4b915342e2a8 LuaSocket 2.0.2 + CMake build description.
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33 int except_open(lua_State *L);
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34
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35 #endif