Limitations

Since the Portal UI is implemented in ClojureScript, it also adopts some of its platform limitations.

Dates

Dates captured from your host platform are interpreted as js/Date in the Portal UI. Therefore, as documents by this ClojureScript issue, they are potentially interpreted against a different calendar.

Longs

Since JavaScript doesn't support the full range of numbers provided by longs, integers outside of a certain range must be boxed and shipped as string to the UI. This precludes them from participating in viewers that expect js/Number.

Doubles

Since Portal serializes values as JSON, the treatment of doubles can become inexact. Any double value submitted to Portal with no decimal component can get "downcast" to a long when rendered or brought back into the REPL. This is further complicated since container values (maps, sets, vectors, lists) are captured and can be returned to the REPL exactly therefore avoiding this issue. In any case, Portal should not be replied upon to preserve exact numeric types.

Lazy Values

Lazy values that contain exceptions will cause Portal's internals to break if allowed to flow into the tap-list. By trying to partially realize lazy values before accepting them, and rejecting any exceptional values, Portal can keep working. However, this only applies to the default tap-list. Since Portal can be opened with any value, it is still possible to break that instance of Portal, but it should be contained to that specific instance.