MARKLESS_CALLBACK_SLOT_UNBOUND

A callback slot is invoked but no component fills it: a Markless compiler warning.

Warning from the compiler, while it builds your .tsrx files.

What happened

Markless prints the message, the reason, and a suggestion:

MARKLESS_CALLBACK_SLOT_UNBOUND: shared() "<definitionName>" invokes its "<slotName>" callback slot, but no component in this module assigns a callback prop into it.
Without an assignment there is no widget root to route the call to, so the invocation can never reach a consumer and does nothing at runtime.
Assign the widget root's callback prop into the slot: <instance>.<slotName> = <thatProp>.
https://markless.dev/errors/MARKLESS_CALLBACK_SLOT_UNBOUND

Words in angle brackets change from case to case.

How to fix it

Start with the suggestion in the message above.

If you accept the warning on purpose, put this comment on the line above it:

// markless-allow MARKLESS_CALLBACK_SLOT_UNBOUND: the reason you accept it

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Where it comes from

@markless/compiler raises this code. Source:

• packages/compiler/src/passes/semantic-graph/diagnostics.ts

Read how to read a Markless error, or go back to all error codes.