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digitalmars.D.learn - stdin.readln line editing and recall with up arrow

reply Daren Scot Wilson <darenw darenscotwilson.com> writes:
stdin.readln() works fine until I, out of habit, use the up arrow 
to recall an earlier input and the left/right to move around and 
change a character.   How do I get that to work?
Feb 24 2023
parent reply "Richard (Rikki) Andrew Cattermole" <richard cattermole.co.nz> writes:
On 25/02/2023 6:36 PM, Daren Scot Wilson wrote:

 stdin.readln() works fine until I, out of habit, use the up arrow to 
 recall an earlier input and the left/right to move around and change a 
 character.   How do I get that to work?


Not with that module.

You can either use GNU readline itself, or Adam's version within arsd.
Feb 24 2023
parent reply Daren Scot Wilson <darenw darenscotwilson.com> writes:
On Saturday, 25 February 2023 at 05:41:48 UTC, Richard (Rikki) 
Andrew Cattermole wrote:

 On 25/02/2023 6:36 PM, Daren Scot Wilson wrote:

 stdin.readln() works fine until I, out of habit, use the up 
 arrow to recall an earlier input and the left/right to move 
 around and change a character.   How do I get that to work?


 Not with that module.

 You can either use GNU readline itself, or Adam's version 
 within arsd.


I went with readline.  Left/right arrows work, but up arrow still 
does not recall earlier commands. Maybe I need also a separate 
input history thing?
Feb 25 2023
next sibling parent reply "Richard (Rikki) Andrew Cattermole" <richard cattermole.co.nz> writes:
On 25/02/2023 9:45 PM, Daren Scot Wilson wrote:

 I went with readline.  Left/right arrows work, but up arrow still does 
 not recall earlier commands. Maybe I need also a separate input history 
 thing?


https://tiswww.case.edu/php/chet/readline/readline.html#Basic-Behavior
Feb 25 2023
parent Daren Scot Wilson <darenw darenscotwilson.com> writes:
On Saturday, 25 February 2023 at 08:47:42 UTC, Richard (Rikki) 
Andrew Cattermole wrote:

 On 25/02/2023 9:45 PM, Daren Scot Wilson wrote:

 I went with readline.  Left/right arrows work, but up arrow 
 still does not recall earlier commands. Maybe I need also a 
 separate input history thing?


 https://tiswww.case.edu/php/chet/readline/readline.html#Basic-Behavior


Hmm... the add_history(), or maybe it's rl_add_history(), 
function seems to have been in ancient readline versions but at 
some point all line history code was taken out to be its own 
library.

https://tiswww.case.edu/php/chet/readline/rltop.html
https://tiswww.case.edu/php/chet/readline/history.html

Arch Linux drags in both readline.so and history.so in its 
readline package. No one notices!


Trying import gnu.history;  fails since there's no distinct 
'history' package (yet) and Dub doesn't drag it in along with 
readline.

D can call C and link to anything in /usr/lib easily. Done. It 
works!   How does D know to link to the libhistory.so library?  I 
didn't say "history" anywhere.  But it works.

     extern (C) {
         void add_history(const char*);
     }


I'm tempted to make a history package and submit it to DUB. 
Maybe. After dinner...
Feb 28 2023
prev sibling parent bachmeier <no spam.net> writes:
On Saturday, 25 February 2023 at 08:45:27 UTC, Daren Scot Wilson 
wrote:

 On Saturday, 25 February 2023 at 05:41:48 UTC, Richard (Rikki) 
 Andrew Cattermole wrote:

 On 25/02/2023 6:36 PM, Daren Scot Wilson wrote:

 stdin.readln() works fine until I, out of habit, use the up 
 arrow to recall an earlier input and the left/right to move 
 around and change a character.   How do I get that to work?


 Not with that module.

 You can either use GNU readline itself, or Adam's version 
 within arsd.


 I went with readline.  Left/right arrows work, but up arrow 
 still does not recall earlier commands. Maybe I need also a 
 separate input history thing?


If you start your program with rlwrap, for example `rlwrap cmd`, 
you'll get that for free.
Feb 25 2023