[Answered] What is ~ used for? [was "~ secrets?"]

This is most likely a stupid question, but I didn’t find an answer in the docs.
(And if it’s a stupid question it should be easy to get an answer )
In php and template code I frequently find the tilde character (~), often in conjunction with "[", for instance [tt]"[~$id~]"[/tt] being magically transformed to index.php?id=##. Or used in a template like [tt]a href="[~[(site_start)]~]"[/tt]
Can someone explain me how that works??

Thanks in advance.

ppaul, the [~ ~] tags are for generating links from the ID of a MODx document. So [~1~] would be replaced with the appropriate link to document with ID = 1; other tags can then be nested, so [(site_start)] is a system setting tag that can be used to create a link to the site_start page, since it returns the document ID of that page, hence [~[(site_start)]~]

Might also check out the AliasLinks plugin for additional ways to build links via a document alias.

Ahh! and it resolves expressions/variables etc which return an id between the ~~ making it easy to create a link.
Good to know.
Thanks Jason for your patience!