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digitalmars.D.learn - Range format specifiers in other languages?

reply =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
I find D's %( and %) range format specifiers very useful:

import std.stdio;
import std.range;

void main() {
   5.iota.writefln!"%(%s, %)";  // Prints 0, 1, 2, 3, 4
}

Are there similar features in other languages?

Thank you,
Ali
Oct 11 2020
next sibling parent reply Max Haughton <maxhaton gmail.com> writes:
On Sunday, 11 October 2020 at 23:57:31 UTC, Ali Çehreli wrote:

 I find D's %( and %) range format specifiers very useful:

 import std.stdio;
 import std.range;

 void main() {
   5.iota.writefln!"%(%s, %)";  // Prints 0, 1, 2, 3, 4
 }

 Are there similar features in other languages?

 Thank you,
 Ali


I think rust can do something similar with struct pretty 
printing. The syntax has curly braces in it but I can't recall it 
right now.

Possibly worth showing off (especially given that some people at 
first don't even know the templated format string exists)
Oct 11 2020
parent =?UTF-8?Q?Ali_=c3=87ehreli?= <acehreli yahoo.com> writes:
On 10/11/20 5:44 PM, Max Haughton wrote:


 Possibly worth showing off (especially given that some people at first
 don't even know the templated format string exists)


This feature is already among my slides for an upcoming conference. ;)

Ali
Oct 11 2020
prev sibling parent reply Imperatorn <johan_forsberg_86 hotmail.com> writes:
On Sunday, 11 October 2020 at 23:57:31 UTC, Ali Çehreli wrote:

 I find D's %( and %) range format specifiers very useful:

 import std.stdio;
 import std.range;

 void main() {
   5.iota.writefln!"%(%s, %)";  // Prints 0, 1, 2, 3, 4
 }

 Are there similar features in other languages?

 Thank you,
 Ali


To people trying to learn, why is that % before ( needed in the 
format string?
Oct 11 2020
parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Monday, 12 October 2020 at 00:46:37 UTC, Imperatorn wrote:

 To people trying to learn, why is that % before ( needed in the 
 format string?


The %( ... %) stuff is expanded and repeated for each element 
inside the given array.
Oct 11 2020
parent reply Imperatorn <johan_forsberg_86 hotmail.com> writes:
On Monday, 12 October 2020 at 00:59:33 UTC, Adam D. Ruppe wrote:

 On Monday, 12 October 2020 at 00:46:37 UTC, Imperatorn wrote:

 To people trying to learn, why is that % before ( needed in 
 the format string?


 The %( ... %) stuff is expanded and repeated for each element 
 inside the given array.


Thanks, it seems there are some pretty powerful formatting 
options:

https://dlang.org/phobos/std_format.html
Oct 11 2020
parent "H. S. Teoh" <hsteoh quickfur.ath.cx> writes:
On Mon, Oct 12, 2020 at 05:51:21AM +0000, Imperatorn via Digitalmars-d-learn
wrote:

 On Monday, 12 October 2020 at 00:59:33 UTC, Adam D. Ruppe wrote:

 On Monday, 12 October 2020 at 00:46:37 UTC, Imperatorn wrote:

 To people trying to learn, why is that % before ( needed in the
 format string?


 
 The %( ... %) stuff is expanded and repeated for each element inside
 the given array.


 
 Thanks, it seems there are some pretty powerful formatting options:
 
 https://dlang.org/phobos/std_format.html


Indeed.

%(...%) is one of my favorite because it can be nested, so it's a very
useful quick-n-dirty tool for debugging ranges. With .chunks and .map,
you can format just about any range-based data in a one-liner for
dumping debug info.

Another cool one is the `,` digit-grouper:

	import std;
	void main() {
		writefln("%,2d", 1234567890);
		writefln("%,3d", 1234567890);
		writefln("%,4d", 1234567890);
		writefln("%,3?d", '_', 1234567890);
		writefln("%,4?d", '\'', 1234567890);
		writefln("%,4?.2f", '\'', 1234567890.123);
	}

Output:
	12,34,56,78,90
	1,234,567,890
	12,3456,7890
	1_234_567_890
	12'3456'7890
	12'3456'7890.12


T

-- 
Век живи - век учись. А дураком помрёшь.
Oct 12 2020