known? (value -- isKnown)

Builtins

Name introduction, declaration modifiers, and module binding: NAME: ...;, codeRef, def, exportFunction, importFunction, importVariable, overload, private, static, use, and virtual.
Struct construction forms: (...), {...}, and array.
Selection forms: source-text selection with NAME and .NAME, read-only source-text selection with @NAME and .@NAME, and ordinal or known-name data-input selection with @, callField, and fieldRead.
Writing forms: source-text selection with !NAME and .!NAME, ordinal selection with ! and fieldWrite, and already-selected destination replacement with set.
Calling and control flow: call, if, loop, ucall, and uif.
Text operations: &, LF, attribute, textSize, and textSplit.
Condition constants, value comparison, and logical operators: <, =, >, DEBUG, FALSE, TRUE, and, is, lshift, or, rshift, xor, and ~.
Arithmetic and numeric transforms: *, +, -, /, ^, cast, ceil, cos, floor, log, log10, mod, neg, sin, and sqrt.
Reference, creation, and value-state operations: const, dynamic, isConst, isDirty, isDynamic, isRef, isStatic, known?, new, newVarOfTheSameType, stable?, unconst, and unknownStable?.
Schema and struct introspection: code?, codeRef?, fieldCount, fieldIndex, fieldIsRef, fieldIsVirtual, fieldName, has, isCombined, managed?, same, schemaName, and virtual?.
Storage and manual lifetime operations: addressToReference, alignment, manuallyDestroyVariable, manuallyInitVariable, storageAddress, and storageSize.
Diagnostics and compile-time failure: failCompilation, getCallTrace, printCompilerMessage, printStack, printStackTrace, and raiseStaticError.

known? (value -- isKnown)

Inputs

value: Current stack value tested by the preferred knownness predicate.

Outputs

isKnown: Known Cond result that is TRUE when the current stack value is fully known at compile time.

known? is the preferred public name of the current stack-value knownness predicate. It tests whether the current stack value is fully known at compile time.

This predicate follows the referenced target for known non-NIL Ref values. It tests compile-time knownness only. Forgotten-contents state and current stability do not by themselves determine the result. Current stack Code values produced by user-visible creation paths such as codeRef, exportFunction, and block assignment to Code still report FALSE. This includes callable non-NIL Code values reached through those paths and known NIL Code values.

Behavior

A fully known In-place value reports TRUE.

An In-place value whose concrete contents have been forgotten, for example by dynamic, reports FALSE.

For Ref values, known? tests whether the referenced target is fully known, not merely whether a non-NIL Ref value exists on the stack.

A known non-NIL Ref value to an unknown target reports FALSE.

Known non-NIL Text values report TRUE, while known NIL and unknown Text values report FALSE.

Meta values report TRUE.

Current stack Code values produced by those user-visible creation paths report FALSE, including callable non-NIL and known NIL Code values.

Example

{} 0 {} [ knownValue: 7; unknownValue: 0 dynamic; unknownText: 0 ("") dynamic @; codeLocal: {} () {} codeRef; [] !codeLocal "-- In-place values --" printCompilerMessage 7 known? printStack _:; 7 isDynamic printStack _:; 7 stable? printStack _:; unknownValue known? printStack _:; unknownValue isDynamic printStack _:; unknownValue stable? printStack _:; "-- references ask about the target too --" printCompilerMessage @knownValue known? printStack _:; @unknownValue known? printStack _:; 0nx knownValue addressToReference known? printStack _:; "-- text, meta, code --" printCompilerMessage "hi" known? printStack _:; 0nx "" addressToReference known? printStack _:; unknownText known? printStack _:; () known? printStack _:; {} () {} codeRef known? printStack _:; {} () {} codeRef dynamic known? printStack _:; @codeLocal known? printStack _:; 0 ] "main" exportFunction

Expected Output During Compilation

-- In-place values -- TRUE FALSE TRUE FALSE TRUE TRUE -- references ask about the target too -- TRUE FALSE FALSE -- text, meta, code -- TRUE FALSE FALSE TRUE FALSE FALSE FALSE