uif (condition trueCallable falseCallable -- branchResult)

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.

uif (condition trueCallable falseCallable -- branchResult)

Inputs

condition: Known Cond that selects the branch.

trueCallable: Already-selected Block processed inline when condition is true.

falseCallable: Already-selected Block processed inline when condition is false.

Outputs

branchResult: Result produced by the selected inline branch.

uif selects between two already-selected Block branches by one known Cond value.

The selected branch is processed inline in the current scope. Locals created there remain available afterward.

Only the selected branch is processed. The unselected branch is ignored completely, may be invalid, and no branch-output merge occurs.

Behavior

condition must be a known Cond value.

Both branch inputs must be Block values already on the data stack.

Any additional data inputs used by a branch must already be below condition, trueCallable, and falseCallable on the data stack.

Before the selected branch is processed, condition, trueCallable, and falseCallable are removed from the stack. The selected branch sees only the remaining underlying data stack.

TRUE selects trueCallable. FALSE selects falseCallable.

Because only one branch is processed, there is no branch-output merge step and the two branches do not need compatible stack outputs.

Example

{} 0 {} [ TRUE [ 7 "chosenTrue" def "-- true branch --" printCompilerMessage ] [ impossibleName ] uif FALSE [ impossibleOtherName ] [ 8 "chosenFalse" def "-- false branch --" printCompilerMessage ] uif "-- after uif --" printCompilerMessage chosenTrue printStack _:; chosenFalse printStack _:; "-- no branch merge --" printCompilerMessage TRUE [1] [FALSE] uif printStack _:; 0 ] "main" exportFunction

Expected Output During Compilation

-- true branch -- -- false branch -- -- after uif -- 7 Cref 8 Cref -- no branch merge -- 1