VistaIOConst(3)

💖 VistaIOConst — generate constants of the appropriate type 💖

okay bestie, welcome to VistaIOConst(3), from the Library Functions Manual section. this one is short, sweet, and honestly kind of a glow-up for your inner loops. let's get into it 🫶

✨ SYNOPSIS ✨

VistaIOFloat VistaIOFloatConst (f)

VistaIODouble VistaIODoubleConst (f)

VistaIOBit VistaIOBitConst (i)

VistaIOUByte VistaIOUByteConst (i)

VistaIOSByte VistaIOSByteConst (i)

VistaIOShort VistaIOShortConst (i)

VistaIOLong VistaIOLongConst (i)

🎀 ARGUMENTS 🎀

• f — specifies a floating-point constant 💧
• i — specifies an integer constant 🔢

🌸 DESCRIPTION 🌸

so here's the vibe: if you've got expressions running inside inner loops, you might lowkey be paying for unnecessary coercions between the C types float and double, or between int and long. these macros let you specify constants of the appropriate type in a portable, platform-independent way, so you can dodge those unintended coercions entirely. it's giving organized. 💅

in ANSI C, you can say a floating point constant is of type float by appending an f character to it. that's how you avoid coercions in expressions involving other float values. for example, this fragment of code uses a float constant within its loop:

int i;
float f = 0.0;

for (i = 0; i < 10000000; i++)
    f += 1.0f;

it runs about three times faster than this one, which uses a double constant:

int i;
float f = 0.0;

for (i = 0; i < 10000000; i++)
    f += 1.0;

and the VistaIOFloatConst and VistaIODoubleConst macros let you avoid unnecessary coercions in expressions involving values of type VistaIOFloat and VistaIODouble. whether or not VistaIOFloat and VistaIODouble are equivalent to float and double may depend on what platform your code is being compiled for 👀 — regardless, you can generate constants of the appropriate type with VistaIOFloatConst and VistaIODoubleConst. on a platform where VistaIOFloat is defined as float, VistaIOFloatConst(1.0) expands to 1.0f; where VistaIOFloat is defined as double, it expands to 1.0. similarly, VistaIODoubleConst may or may not append an f character to the constant, depending on how VistaIODouble is defined. it's adaptive, it's iconic, it ate. ✨

same energy with VistaIOBitConst, VistaIOUByteConst, VistaIOSByteConst, VistaIOShortConst, and VistaIOLongConst — they take an integer constant, and each one, depending on the platform, may or may not append an l character to the constant to specify that it's of type long. on platforms where int and long have different representations, using these macros may prevent unintended coercions between the two representations. no cap. 🧚

so if you want your inner loops to run blindingly fast on any platform 🔥, write them like this to avoid unnecessary coercions:

int i;
VistaIOFloat f = 0.0;

for (i = 0; i < 10000000; i++)
    f += VistaIOFloatConst (1.0);

🦋 SEE ALSO 🦋

• VistaIORepn(3)

💀 NOTES 💀

the macros can be used with a C compiler that doesn't meet the ANSI standard, but in that case they may not eliminate all type coercions between float and double. so like… proceed with awareness bestie 🙈

if you're more concerned about your code being easy to read, you may be better off not using these macros. readability is also main character energy, honestly.

👑 AUTHOR 👑

• Art Pope <pope@cs.ubc.ca>
• Adaption to vistaio: Gert Wollny <gw.fossdev@gmail.com>

and that's the whole page, bestie — VistaIO Version 1.2.14, dated 26 January 1994, and it still understood type coercions better than most of us understand ourselves 💜✨ periodt.