Convert and format values

str.from converts numbers or booleans to text, returning Result[str, AllocError]. Floats use the shortest text that parses back to the same value.

def main() -> Result[(), AllocError | IoError]:
    print(str.from(42)?)?
    print(str.from(-0.0f32)?)?
    print(str.from(True)?)?
    Ok(())

42
-0.0
True

Inspect a value with str.repr

str.repr formats a borrowed value; print writes a value and newline, reporting formatting allocation failures and output errors:

def main() -> Result[(), AllocError | IoError]:
    values = [1, 2]?
    print(str.repr(values)?)?
    print(values)?
    Ok(())

[1, 2]
[1, 2]

Formatting failure writes nothing. An output error can leave a partial write. The source remains usable; neither call copies a mutable collection.

The inner ? handles formatting; the outer ? handles printing. To inspect a Result wrapper itself, pass it to str.repr:

def main() -> Result[(), AllocError | IoError]:
    result: Result[i64, str] = Err("not ready")
    print(str.repr(result)?)?
    Ok(())

Result[i64, str].Err("not ready")