Category:Tcl: Difference between revisions

* Practically, values are polymorphic and hold a cache of the last type-interpretation that they were used with, together with an optional [[UTF-8]] string representation. They are reference -counted and are not modifiable (unless the code in question holds the only reference, which is a significant efficiency gain; if the value is shared, it is shallow-copied upon modification). Although only reference -counted, they are effectively garbage-collected since circular data structures cannot be constructed (performing such construction requires holding two references to the same object, which forces a copy to be taken and breaks the reference loop). The net effect of this is just like the UNICODE string classical model, except much faster.