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TimeKeeper 0.0.1

The html source will be appended a report with different times of executions for precise parts of your Vanilla scripts.
At any point in your code, add a line like:
if (!empty( $Context->TimeKeeper )) $Context->TimeKeeper->AddMarker( 'a step in execution' );
Time elapsed between this one and the previous one will be displayed in the report.

You can define the format of this report through constants at the beginning of the default.php file: TK_PREFIX, TK_SUFFIX, TK_ITEM_FORMAT and TK_DECIMALS. It will only be seen by people having a normal Vanilla permission (that you can set as you wish).
This report is (at the moment) after the </html> tag, so your document will NOT validate.

NOTE: This is not a REAL extension as we usually encounter in Vanilla. TimeKeeper needs little hacks to the core, so you have to be used to PHP and to Vanilla for a correct installation.