cast (value schema -- convertedValue)

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.

cast (value schema -- convertedValue)

Inputs

value: Cond or numeric value to convert.

schema: Numeric schema selector.

Outputs

convertedValue: Converted numeric value.

cast converts a Cond or numeric value to the selected numeric schema.

The schema input is used only as a numeric schema selector. Its value is not read.

Behavior

Cond converts to numeric through TRUE = 1 and FALSE = 0, then follows the selected numeric schema.

Whole-to-Whole conversion extends, truncates, or preserves and reinterprets the bit pattern according to source width, target width, and source signedness.

Whole-number to Real conversion converts numerically to the selected real schema.

Real to Whole conversion converts numerically to the selected Whole schema and truncates toward zero.

Real to Real conversion widens or narrows precision as needed.

Known input values are cast at compile time.

Unknown inputs produce unknown values in the selected schema.

Example

{} 0 {} [ "-- schema selector value ignored --" printCompilerMessage 7 0n8 cast printStack _:; 7 255n8 cast printStack _:; targetNat: 255n8 dynamic; 7 targetNat cast printStack _:; TRUE 0i16 cast printStack _:; TRUE -1i16 cast printStack _:; FALSE 0i16 cast printStack _:; FALSE -1i16 cast printStack _:; "-- whole to whole width and signedness --" printCompilerMessage -1 0n8 cast printStack _:; 255n8 0i8 cast printStack _:; -1i8 0i16 cast printStack _:; 255n8 0n16 cast printStack _:; "-- real to whole truncates toward zero --" printCompilerMessage 7.9r32 0 cast printStack _:; -7.9r32 0 cast printStack _:; "-- unknown value --" printCompilerMessage value: 0 dynamic; value 123.0r32 cast printStack _:; 0 ] "main" exportFunction

Expected Output During Compilation

-- schema selector value ignored -- 7n8 7n8 7n8 1i16 1i16 0i16 0i16 -- whole to whole width and signedness -- 255n8 -1i8 -1i16 255n16 -- real to whole truncates toward zero -- 7 -7 -- unknown value -- Real32