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diff --git a/phpBB/docs/codingstandards.htm b/phpBB/docs/codingstandards.htm deleted file mode 100644 index 1cb7f3c57d..0000000000 --- a/phpBB/docs/codingstandards.htm +++ /dev/null @@ -1,327 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<!-- saved from url=(0044) --> -<HTML><HEAD><TITLE>phpBB Coding Standard Guidelines</TITLE> -<META content="text/html; charset=windows-1252" http-equiv=Content-Type> -<META content="MSHTML 5.00.2920.0" name=GENERATOR></HEAD> -<BODY aLink=#cccccc bgColor=#ffffff link=#0000ff text=#000000 -vLink=#0000ff><FONT face=verdana,arial,tahoma size=-1><A name=top></A> -<H2>phpBB Coding Standard Guidelines</H2>Comments or suggestions? email <A -href="mailto:nate@phpbb.com">nate@phpbb.com</A><BR><BR><A -href="#editor">Editor -Settings</A><BR><A -href="#naming">Naming -Conventions</A><BR><A -href="#layout">Code Layout</A><BR><A -href="#general">General -Guidelines</A><BR><BR><BR><A name=editor></A><A -href="#top">top</A> -<H3>Editor Settings</H3> -<P><B>Tabs vs Spaces:</B> In order to make this as simple as possible, we will -be using tabs, not spaces. Feel free to set how many spaces your editor uses -when it <B>displays</B> tabs, but make sure that when you <B>save</B> the file, -it's saving tabs and not spaces. This way, we can each have the code be -displayed the way we like it, without breaking the layout of the actual files. -</P> -<P><B>Linefeeds:</B> Ensure that your editor is saving files in the UNIX format. -This means lines are terminated with a newline, not with a CR/LF combo as they -are on Win32, or whatever the Mac uses. Any decent Win32 editor should be able -to do this, but it might not always be the default. Know your editor. If you -want advice on Windows text editors, just ask one of the developers. Some of -them do their editing on Win32. </P><BR><BR><A name=naming></A><A -href="#top">top</A> -<H3>Naming Conventions</H3> -<P>We will not be using any form of hungarian notation in our naming -conventions. Many of us believe that hungarian naming is one of the primary code -obfuscation techniques currently in use. </P> -<P><B>Variable Names:</B> Variable names should be in all lowercase, with words -separated by an underscore. <BR><BR> Example: <CODE><FONT -size=+1>$current_user</FONT></CODE> is right, but <CODE><FONT -size=+1>$currentuser</FONT></CODE> and <CODE><FONT -size=+1>$currentUser</FONT></CODE> are not. <BR><BR>Names should be descriptive, -but concise. We don't want huge sentences as our variable names, but typing an -extra couple of characters is always better than wondering what exactly a -certain variable is for. </P> -<P><B>Loop Indices:</B> The <I>only</I> situation where a one-character variable -name is allowed is when it's the index for some looping construct. In this case, -the index of the outer loop should always be $i. If there's a loop inside that -loop, its index should be $j, followed by $k, and so on. If the loop is being -indexed by some already-existing variable with a meaningful name, this guideline -does not apply. <BR><BR> Example: <PRE><FONT size=+1> - for ($i = 0; $i < $outer_size; $i++) - { - for ($j = 0; $j < $inner_size; $j++) - { - foo($i, $j); - } - } </FONT></PRE> -<P></P> -<P><B>Function Names:</B> Functions should also be named descriptively. We're -not programming in C here, we don't want to write functions called things like -"stristr()". Again, all lower-case names with words separated by a single -underscore character. Function names should preferably have a verb in them -somewhere. Good function names are <CODE><FONT -size=+1>print_login_status()</FONT></CODE>, <CODE><FONT -size=+1>get_user_data()</FONT></CODE>, etc.. </P> -<P><B>Function Arguments:</B> Arguments are subject to the same guidelines as -variable names. We don't want a bunch of functions like: <CODE><FONT -size=+1>do_stuff($a, $b, $c)</FONT></CODE>. In most cases, we'd like to be able -to tell how to use a function by just looking at its declaration. </P> -<P><B>Summary:</B> The basic philosophy here is to not hurt code clarity for the -sake of laziness. This has to be balanced by a little bit of common sense, -though; <CODE><FONT size=+1>print_login_status_for_a_given_user()</FONT></CODE> -goes too far, for example -- that function would be better named <CODE><FONT -size=+1>print_user_login_status()</FONT></CODE> , or just <CODE><FONT -size=+1>print_login_status()</FONT></CODE>. </P><BR><BR><A name=layout></A><A -href="#top">top</A> -<H3>Code Layout</H3> -<P><B>Standard header for new files:</B> Here a template of the header that must -be included at the start of all phpBB files: <PRE><FONT size=+1> - /*************************************************************************** - filename.php - ------------------- - begin : Sat June 17 2000 - copyright : (C) 2000 The phpBB Group - email : support@phpBB.com - - $Id$ - - ***************************************************************************/ - - /*************************************************************************** - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - ***************************************************************************/ - </FONT></PRE> -<P></P> -<P><B>Always include the braces:</B> This is another case of being too lazy to -type 2 extra characters causing problems with code clarity. Even if the body of -some construct is only one line long, do <I>not</I> drop the braces. Just don't. -<BR><BR> Examples:<PRE><FONT size=+1> - /* These are all wrong. */ - if (condition) do_stuff(); - if (condition) - do_stuff(); - while (condition) - do_stuff(); - for ($i = 0; $i < size; $i++) - do_stuff($i); - - /* These are right. */ - if (condition) - { - do_stuff(); - } - while (condition) - { - do_stuff(); - } - for ($i = 0; $i < size; $i++) - { - do_stuff(); - } - </FONT></PRE> -<P></P> -<P><B>Where to put the braces:</B> This one is a bit of a holy war, but we're -going to use a style that can be summed up in one sentence: Braces always go on -their own line. The closing brace should also always be at the same column as -the corresponding opening brace. <BR><BR> Examples:<PRE><FONT size=+1> - if (condition) - { - while (condition2) - { - ... - } - } - else - { - ... - } - - for ($i = 0; $i < $size; $i++) - { - ... - } - - while (condition) - { - ... - } - - function do_stuff() - { - ... - } - </FONT></PRE> -<P></P> -<P><B>Use spaces between tokens:</B> This is another simple, easy step that -helps keep code readable without much effort. Whenever you write an assignment, -expression, etc.. Always leave <I>one</I> space between the tokens. Basically, -write code as if it was English. Put spaces between variable names and -operators. Don't put spaces just after an opening bracket or before a closing -bracket. Don't put spaces just before a comma or a semicolon. This is best shown -with a few examples. <BR><BR> Examples:<PRE><FONT size=+1> - /* Each pair shows the wrong way followed by the right way. */ - - $i=0; - $i = 0; - - if($i<7) ... - if ($i < 7) ... - - if ( ($i < 7)&&($j > 8) ) ... - if (($i < 7) && ($j > 8)) ... - - do_stuff( $i, "foo", $b ); - do_stuff($i, "foo", $b); - - for($i=0; $i<$size; $i++) ... - for($i = 0; $i < $size; $i++) ... - - $i=($j < $size)?0:1; - $i = ($j < $size) ? 0 : 1; - </FONT></PRE> -<P></P> -<P><B>Operator precedence:</B> Do you know the exact precedence of all the -operators in PHP? Neither do I. Don't guess. Always make it obvious by using -brackets to force the precedence of an equation so you know what it does. -<BR><BR> Examples:<PRE><FONT size=+1> - /* what's the result? who knows. */ - $bool = ($i < 7 && $j > 8 || $k == 4); - - /* now you can be certain what I'm doing here. */ - $bool = (($i < 7) && (($j < 8) || ($k == 4))) - </FONT></PRE> -<P></P> -<P><B>SQL code layout:</B> Since we'll all be using different editor settings, -don't try to do anything complex like aligning columns in SQL code. Do, however, -break statements onto their own lines. Here's a sample of how SQL code should -look. Note where the lines break, the capitalization, and the use of brackets. -<BR><BR> Examples:<PRE><FONT size=+1> - SELECT field1 AS something, field2, field3 - FROM table a, table b - WHERE (this = that) AND (this2 = that2) - </FONT></PRE> -<P></P> -<P><B>SQL insert statements:</B> SQL INSERT statements can be written in two -different ways. Either you specify explicitly the columns being inserted, or -you rely on knowing the order of the columns in the database and do not -specify them. We want to use the former approach, where it is explicitly -stated whcih columns are being inserted. This means our application-level code -will not depend on the order of the fields in the database, and will not be broken -if we add additional fields (unless they're specified as NOT NULL, of course). -<BR><BR> Examples:<PRE><FONT size=+1> - # This is not what we want. - INSERT INTO mytable - VALUES ('something', 1, 'else') - - # This is correct. - INSERT INTO mytable (column1, column2, column3) - VALUES ('something', 1, 'else') - </FONT></PRE> -<P></P><BR><BR><A name=general></A><A -href="#top">top</A> -<H3>General Guidelines</H3> -<P><B>Quoting strings:</B> There are two different ways to quote strings in PHP -- either with single quotes or with double quotes. The main difference is that -the parser does variable interpolation in double-quoted strings, but not in -single quoted strings. Because of this, you should <I>always</I> use single -quotes <I>unless</I> you specifically need variable interpolation to be done on -that string. This way, we can save the parser the trouble of parsing a bunch of -strings where no interpolation needs to be done. Also, if you are using a string -variable as part of a function call, you do not need to enclose that variable in -quotes. Again, this will just make unnecessary work for the parser. Note, -however, that nearly all of the escape sequences that exist for double-quoted -strings will not work with single-quoted strings. Be careful, and feel free to -break this guideline if it's making your code harder to read. -<BR><BR> Examples:<PRE><FONT size=+1> - /* wrong */ - $str = "This is a really long string with no variables for the parser to find."; - do_stuff("$str"); - - /* right */ - $str = 'This is a really long string with no variables for the parser to find.'; - do_stuff($str); - </FONT></PRE> -<P></P> -<P><B>Associative array keys:</B> In PHP, it's legal to use a literal string as -a key to an associative array without quoting that string. We don't want to do -this -- the string should always be quoted to avoid confusion. Note that this is -only when we're using a literal, not when we're using a variable. -<BR><BR> Examples:<PRE><FONT size=+1> - /* wrong */ - $foo = $assoc_array[blah]; - - /* right */ - $foo = $assoc_array['blah']; - </FONT></PRE> -<P></P> -<P><B>Comments:</B> Each function should be preceded by a comment that tells a -programmer everything they need to know to use that function. The meaning of -every parameter, the expected input, and the output are required as a minimal -comment. The function's behaviour in error conditions (and what those error -conditions are) should also be present. Nobody should have to look at the actual -source of a function in order to be able to call it with confidence in their own -code. <BR><BR>In addition, commenting any tricky, obscure, or otherwise -not-immediately-obvious code is clearly something we should be doing. Especially -important to document are any assumptions your code makes, or preconditions for -its proper operation. Any one of the developers should be able to look at any -part of the application and figure out what's going on in a reasonable amount of -time. </P> -<P><B>Magic numbers:</B> Don't use them. Use named constants for any literal -value other than obvious special cases. Basically, it's OK to check if an array -has 0 elements by using the literal 0. It's not OK to assign some special -meaning to a number and then use it everywhere as a literal. This hurts -readability AND maintainability. Included in this guideline is that we should be -using the constants TRUE and FALSE in place of the literals 1 and 0 -- even -though they have the same values, it's more obvious what the actual logic is -when you use the named constants. </P> -<P><B>Shortcut operators:</B> The only shortcut operators that cause readability -problems are the shortcut increment ($i++) and decrement ($j--) operators. These -operators should not be used as part of an expression. They can, however, be -used on their own line. Using them in expressions is just not worth the -headaches when debugging. <BR><BR> Examples:<PRE><FONT size=+1> - /* wrong */ - $array[++$i] = $j; - $array[$i++] = $k; - - - /* right */ - $i++; - $array[$i] = $j; - - $array[$i] = $k; - $i++; - </FONT></PRE> -<P></P> -<P><B>Inline conditionals:</B> Inline conditionals should only be used to do -very simple things. Preferably, they will only be used to do assignments, and -not for function calls or anything complex at all. They can be harmful to -readability if used incorrectly, so don't fall in love with saving typing by -using them. <BR><BR> Examples:<PRE><FONT size=+1> - /* Bad place to use them */ - (($i < $size) && ($j > $size)) ? do_stuff($foo) : do_stuff($bar); - - - /* OK place to use them */ - $min = ($i < $j) ? $i : $j; - </FONT></PRE> -<P></P> -<P><B>Don't use uninitialized variables.</B> for phpBB 2, we intend to use a -higher level of run-time error reporting. This will mean that the use of an -uninitialized variable will be reported as an error. This will come up most -often when checking which HTML form variables were passed. These errors can be -avoided by using the built-in isset() function to check whether a variable has -been set. <BR><BR> Examples:<PRE><FONT size=+1> - /* Old way */ - if ($forum) ... - - - /* New way */ - if (isset($forum)) ... - </FONT></PRE> -<P></P><BR><BR><A href="#top">Return -to top</A> </FONT></BODY></HTML> |