http://wiki.lostsouls.org/w/index.php?action=history&feed=atom&title=Man_block 2026-05-05T14:05:13Z Revision history for this page on the wiki MediaWiki 1.8.2 http://wiki.lostsouls.org/w/index.php?title=Man_block&diff=3953&oldid=prev 2007-06-11T19:10:23Z

<p></p> <p><b>New page</b></p><div>==Description==<br /> <br /> A block is a special statment, that begins with '{', contains<br /> a list of statements, and ends with '}'.<br /> <br /> The block may define local variables. If for a variable no<br /> initialisation is given, the variable is initialised to 0 every<br /> time the block is entered. Otherwise, the initialisation<br /> expression is evaluated and its result assigned to the variable<br /> everytime the block is entered.<br /> <br /> Example definitions are:<br /> <br /> int i;<br /> int j = 3;<br /> int k = 3 * j, l;<br /> <br /> Here, i and l are both initialised to 0; j is initialised<br /> to 3, and k is initialised to 9 (3 * j).<br /> <br /> Local variables defined in a block are visible only until the<br /> end of the block. Definitions in an inner block hide definitions in<br /> outer blocks.<br /> <br /> ==History==<br /> <br /> Up to 3.2.7, local variables were visible (from their point of<br /> definition) in the whole function. That is, code like<br /> <br /> do {<br /> int res;<br /> <br /> res = ...<br /> } while (res == 5);<br /> write(res);<br /> <br /> was perfectly legal. It is no longer, as 'res' ceases to exist<br /> with the closing '}' of the while().<br /> <br /> You can get this old behaviour back with the #pragma no_local_scopes.<br /> To turn it off again, use #pragma local_scopes.<br /> <br /> Up to 3.2.8, local variables could not be initialised in their<br /> definition.</div>

Laine