stable? (value -- isStable)

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.

stable? (value -- isStable)

Inputs

value: Current stack value whose stability is tested.

Outputs

isStable: Known Cond result that is TRUE when the current stack value is stable.

stable? is the current stack-value stability predicate. It tests whether the current stack value is currently stable.

This predicate follows the referenced target for known non-NIL Ref values. It is the exact opposite of isDirty. Compile-time knownness and forgotten-contents state do not by themselves determine the result. Current stack Code values are tested by the current Code value itself, not by callability. User-visible creation paths such as codeRef and block assignment to Code still report FALSE.

Behavior

A fully known or forgotten-contents In-place value reports TRUE.

A known non-NIL Ref value reports the current stability of its referenced target. This follows target stability, not target knownness.

Known NIL Ref values and unknown Ref values report FALSE.

Text values report TRUE only when they are known and non-NIL.

Code values are tested by the current Code value itself, not by callability. User-visible creation paths such as codeRef and block assignment to Code still report FALSE.

Meta values report TRUE.

Example

{} 0 {} [ value: 7; unknownValue: 0 dynamic; unknownText: 0 ("") dynamic @; codeLocal: {} () {} codeRef; [] !codeLocal "-- current stability versus forgotten-contents stability --" printCompilerMessage 7 known? printStack _:; 7 stable? printStack _:; 7 unknownStable? printStack _:; 7 isDynamic printStack _:; unknownValue known? printStack _:; unknownValue stable? printStack _:; unknownValue unknownStable? printStack _:; unknownValue isDynamic printStack _:; "-- references --" printCompilerMessage @value stable? printStack _:; @value unknownStable? printStack _:; @value isDynamic printStack _:; @unknownValue stable? printStack _:; @unknownValue unknownStable? printStack _:; @unknownValue isDynamic printStack _:; 0nx value addressToReference stable? printStack _:; 0nx value addressToReference unknownStable? printStack _:; 0nx value addressToReference isDynamic printStack _:; "-- text, code, meta --" printCompilerMessage "hi" stable? printStack _:; "hi" unknownStable? printStack _:; "hi" isDynamic printStack _:; unknownText stable? printStack _:; unknownText unknownStable? printStack _:; unknownText isDynamic printStack _:; {} () {} codeRef stable? printStack _:; {} () {} codeRef unknownStable? printStack _:; {} () {} codeRef isDynamic printStack _:; @codeLocal stable? printStack _:; () stable? printStack _:; () unknownStable? printStack _:; () isDynamic printStack _:; 0 ] "main" exportFunction

Expected Output During Compilation

-- current stability versus forgotten-contents stability -- TRUE TRUE FALSE FALSE FALSE TRUE TRUE TRUE -- references -- TRUE FALSE FALSE TRUE TRUE TRUE FALSE FALSE FALSE -- text, code, meta -- TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE