cast (object schema -- convertedValue)

Inputs

• object: Cond or numeric object to convert.
• schema: Numeric schema selector.

Outputs

• convertedValue: Converted numeric object.

cast converts a Cond or numeric object 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 objects 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

See also

• ^ builtin (base exponent -- power) Raises one Real object to another of the same schema and keeps that real schema in the result.
• ceil builtin (object -- ceilingValue) Rounds a Real object upward and keeps the same real schema.
• cos builtin (angle -- cosine) Computes the cosine of a Real object and keeps the same real schema.
• floor builtin (object -- floorValue) Rounds a Real object downward and keeps the same real schema.
• log builtin (argument -- naturalLogarithm) Computes the natural logarithm of a Real object and keeps the same real schema.
• log10 builtin (argument -- decimalLogarithm) Computes the base-10 logarithm of a Real object and keeps the same real schema.
• neg builtin (object -- negatedValue) Negates a signed Int or Real object and keeps the same schema.
• sin builtin (angle -- sine) Computes the sine of a Real object and keeps the same real schema.
• sqrt builtin (radicand -- squareRoot) Computes the square root of a Real object and keeps the same real schema.