Tcl_PrintDouble(3tcl)

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version 9.0.4 · 2 versions
, in debian trixie, ubuntu questing, ubuntu resolute, ubuntu stonking

✨ Tcl_PrintDouble — the Tcl Library Procedures era ✨

okay so bestie, we're diving into a Tcl Library Procedures classic, Tcl_PrintDouble(3tcl), and honestly? it's giving humble-but-essential. she takes a float and turns it into a string. that's it. that's the whole job. and she does it flawlessly. 💅

🌸 NAME 🌸

Tcl_PrintDouble — convert floating value to string 🦋

🎀 SYNOPSIS 🎀

#include <tcl.h>

Tcl_PrintDouble(interp, value, dst)

💖 ARGUMENTS 💖

  • Tcl_Interp *interp (in) — bestie, this one is literally just vibing. This argument is ignored. she's there for the plot, not the function. 🙈
  • double value (in) — the floating-point value getting converted. the main character, fr. 👑
  • char *dst (out) — where the string representing value gets stored. and listen, she needs room to breathe: this buffer must have at least TCL_DOUBLE_SPACE characters of storage. no cap, don't skimp on this or you're gonna have a bad time. 💀

✨ DESCRIPTION ✨

Tcl_PrintDouble generates a string that represents the value of value and stores it in memory at the location given by dst. simple. iconic. ✨

She uses %g format to generate the string, but with one special twist that's lowkey the whole personality: the string is guaranteed to contain either a . or an e, so it never gets mistaken for an integer. like, imagine being a double and getting read as an int. embarrassing. 🙈 so wherever %g would produce an integer with no decimal point, Tcl_PrintDouble just adds .0. slay. 💅

The result will have the fewest digits needed to represent the number in such a way that Tcl_NewDoubleObj will generate the same number when presented with the given string. efficiency queen. 🌈 and highkey important: IEEE semantics of rounding to even apply to the conversion. that's just how she operates, periodt.

ngl bestie, the round-trip guarantee is the whole point here — fewest digits, but Tcl_NewDoubleObj still gets back the exact same number. that's the flex. 🔥

🔑 KEYWORDS 🔑

conversion, double-precision, floating-point, string

and that's the page, bestie 🫶 go forth and print those doubles with confidence, you absolute legend. mwah. 💜

Tcl 8.0 · Tcl_PrintDouble(3tcl) · sending you all the float-y love, bye babes 🎀✨

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