bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Mark Karpov]

In Common Lisp there is ‘constantly’ function:

  http://www.lispworks.com/documentation/HyperSpec/Body/f_cons_1.htm

which creates new function without side-effects that takes any number of
arguments and always returns specified value.

For some reason ‘cl-lib’ doesn't provide ‘cl-constantly’, so I guess it
should exist in pure Emacs Lisp under different name. However, I
couldn't find such a function, so I ask you to tell me name of function
that word like ‘constantly’ in Emacs Lisp or add ‘cl-constantly’ in
‘cl-lib’ in Emacs 25.



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bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

Maybe we can add 'constantly' to Emacs outside the cl package.

-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.

bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Nicolas Petton]

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Richard Stallman <rms@gnu.org> writes:

> [[[ To any NSA and FBI agents reading my email: please consider    ]]]
> [[[ whether defending the US Constitution against all enemies,     ]]]
> [[[ foreign or domestic, requires you to follow Snowden's example. ]]]
>
> Maybe we can add 'constantly' to Emacs outside the cl package.

Do you mean as a standard documented function, in subr.el?  Or maybe in
subr-x.el?

Nico

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bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > > Maybe we can add 'constantly' to Emacs outside the cl package.

  > Do you mean as a standard documented function

Yes.

What file to put it in is a detail I am not addressing.

-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.

bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Daniel Colascione]

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On 10/01/2015 07:27 PM, Richard Stallman wrote:
> [[[ To any NSA and FBI agents reading my email: please consider    ]]]
> [[[ whether defending the US Constitution against all enemies,     ]]]
> [[[ foreign or domestic, requires you to follow Snowden's example. ]]]
> 
>   > > Maybe we can add 'constantly' to Emacs outside the cl package.
> 
>   > Do you mean as a standard documented function
> 
> Yes.
> 
> What file to put it in is a detail I am not addressing.

I thought we weren't adding unnamespaced functions anymore.


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bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]

  > I thought we weren't adding unnamespaced functions anymore.

For a general-purpose useful function, such as this one, that is 
the way to add it -- if we are going to add it.


-- 
Dr Richard Stallman
President, Free Software Foundation (gnu.org, fsf.org)
Internet Hall-of-Famer (internethalloffame.org)
Skype: No way! See stallman.org/skype.html.

bug#21584: 25.0.50; Please add cl-constantly function from Common Lisp

[Lars Ingebrigtsen]

Mark Karpov <markkarpov@openmailbox.org> writes:

> In Common Lisp there is ‘constantly’ function:
>
>   http://www.lispworks.com/documentation/HyperSpec/Body/f_cons_1.htm
>
> which creates new function without side-effects that takes any number of
> arguments and always returns specified value.
>
> For some reason ‘cl-lib’ doesn't provide ‘cl-constantly’, so I guess it
> should exist in pure Emacs Lisp under different name.

I've now added `cl-constantly' to Emacs 29.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no