[NTG-context] *Not* starting a section at the very bottom of a page

[NTG-context] *Not* starting a section at the very bottom of a page

[Jim]

This could be a bug report, but it is mostly a request for assistance.

In
   https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
I see "2.11 Big operators" is at the very bottom of a page (no "content" of
section 2.11 is on that page).  This is an example of what I don't want,
and anyone who feels the same way would consider this a (very minor) bug
report for the (otherwise most excellent) math manual.

For plain TeX, I have been using a macro I wrote called \need, so that
a usage like
        \need 2cm
would end the current page before omitting any more material, if there is
less than 2cm left on the current page.  I then used this in chapter and
section macros (and anywhere else I felt like).

I have played around a little bit with converting that macro for ConTeXt,
but I'm not as confident that it Does The Right Thing in ConTeXt as for
plain TeX.

Q: is there a ConTeXt macro which does a \page if there is less space on
   the current page than specified by the argument to the macro?

Thanks.

                                Jim
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________

[NTG-context] Re: *Not* starting a section at the very bottom of a page

[Aditya Mahajan]

On Thu, 24 Apr 2025, Jim wrote:

> This could be a bug report, but it is mostly a request for assistance.
> 
> In
>    https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
> I see "2.11 Big operators" is at the very bottom of a page (no "content" of
> section 2.11 is on that page).  This is an example of what I don't want,
> and anyone who feels the same way would consider this a (very minor) bug
> report for the (otherwise most excellent) math manual.
> 
> For plain TeX, I have been using a macro I wrote called \need, so that
> a usage like
>         \need 2cm
> would end the current page before omitting any more material, if there is
> less than 2cm left on the current page.  I then used this in chapter and
> section macros (and anywhere else I felt like).
> 
> I have played around a little bit with converting that macro for ConTeXt,
> but I'm not as confident that it Does The Right Thing in ConTeXt as for
> plain TeX.
> 
> Q: is there a ConTeXt macro which does a \page if there is less space on
>    the current page than specified by the argument to the macro?

\testpage[n]

will check if there is space for at least n "lines"; if not it will issue a pagebreak. So, you can use it as

\testpage[4] 

to test for 4 lines, etc.

Aditya
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________

[NTG-context] Re: *Not* starting a section at the very bottom of a page

[Hans Hagen]

On 4/24/2025 5:00 PM, Jim wrote:
> This could be a bug report, but it is mostly a request for assistance.
> 
> In
>     https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
> I see "2.11 Big operators" is at the very bottom of a page (no "content" of
> section 2.11 is on that page).  This is an example of what I don't want,
> and anyone who feels the same way would consider this a (very minor) bug
> report for the (otherwise most excellent) math manual.
> 
> For plain TeX, I have been using a macro I wrote called \need, so that
> a usage like
>          \need 2cm
> would end the current page before omitting any more material, if there is
> less than 2cm left on the current page.  I then used this in chapter and
> section macros (and anywhere else I felt like).
> 
> I have played around a little bit with converting that macro for ConTeXt,
> but I'm not as confident that it Does The Right Thing in ConTeXt as for
> plain TeX.
> 
> Q: is there a ConTeXt macro which does a \page if there is less space on
>     the current page than specified by the argument to the macro?

\testpage[3] % lines or some dimension

It's typically something you only do when the document is final.

Hans

-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
        tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________

[NTG-context] Re: *Not* starting a section at the very bottom of a page

[Jim]

Aditya,

thanks for the fast reply.

On Thu, Apr 24, 2025 at 17:08 (+0200), Hans Hagen wrote:

> On 4/24/2025 5:00 PM, Jim wrote:
>> This could be a bug report, but it is mostly a request for assistance.

>> In
>> https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
>> I see "2.11 Big operators" is at the very bottom of a page (no "content" of
>> section 2.11 is on that page).  This is an example of what I don't want,
>> and anyone who feels the same way would consider this a (very minor) bug
>> report for the (otherwise most excellent) math manual.

>> For plain TeX, I have been using a macro I wrote called \need, so that
>> a usage like
>>          \need 2cm
>> would end the current page before omitting any more material, if there is
>> less than 2cm left on the current page.  I then used this in chapter and
>> section macros (and anywhere else I felt like).

>> I have played around a little bit with converting that macro for ConTeXt,
>> but I'm not as confident that it Does The Right Thing in ConTeXt as for
>> plain TeX.

>> Q: is there a ConTeXt macro which does a \page if there is less space on
>> the current page than specified by the argument to the macro?

> \testpage[3] % lines or some dimension

> It's typically something you only do when the document is final.

Hans,

thanks for the almost-as-fast-as-Aditya reply.

I am a bit puzzled by your "It's typically..." comment, for two reasons.
(1) When the document is (almost) final, I could just get out the "\page"
    sledgehammer and whack away with that.
(2) The "bad" page break for Section 2.11 only occurs (at present) in the
    "screen" version, but not in the "paper" version.  To fix the screen
    version, on could (I suppose) do
        \ifthisisthescreenversion
        \page
        \fi
        ... command to start Section 2.11 ...
    but just putting
        \testpage[5] % or whatever number one likes
        ... command to start Section 2.11 ...
    takes care of both formats.

Bonus puzzlement reason: while some documents do indeed become final, I'd
hazard a guess that the majority of documents get updated many times after
their first "release into the wild".

In any case, thanks very much for the information.

                                Jim
    
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________

[NTG-context] Re: *Not* starting a section at the very bottom of a page

[Wolfgang Schuster]

Am 24.04.2025 um 18:04 schrieb Jim:
> Aditya,
> 
> thanks for the fast reply.
> 
> On Thu, Apr 24, 2025 at 17:08 (+0200), Hans Hagen wrote:
> 
>> On 4/24/2025 5:00 PM, Jim wrote:
>>> This could be a bug report, but it is mostly a request for assistance.
> 
>>> In
>>> https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
>>> I see "2.11 Big operators" is at the very bottom of a page (no "content" of
>>> section 2.11 is on that page).  This is an example of what I don't want,
>>> and anyone who feels the same way would consider this a (very minor) bug
>>> report for the (otherwise most excellent) math manual.
> 
>>> For plain TeX, I have been using a macro I wrote called \need, so that
>>> a usage like
>>>           \need 2cm
>>> would end the current page before omitting any more material, if there is
>>> less than 2cm left on the current page.  I then used this in chapter and
>>> section macros (and anywhere else I felt like).
> 
>>> I have played around a little bit with converting that macro for ConTeXt,
>>> but I'm not as confident that it Does The Right Thing in ConTeXt as for
>>> plain TeX.
> 
>>> Q: is there a ConTeXt macro which does a \page if there is less space on
>>> the current page than specified by the argument to the macro?
> 
>> \testpage[3] % lines or some dimension
> 
>> It's typically something you only do when the document is final.
> 
> Hans,
> 
> thanks for the almost-as-fast-as-Aditya reply.
> 
> I am a bit puzzled by your "It's typically..." comment, for two reasons.
> (1) When the document is (almost) final, I could just get out the "\page"
>      sledgehammer and whack away with that.
> (2) The "bad" page break for Section 2.11 only occurs (at present) in the
>      "screen" version, but not in the "paper" version.  To fix the screen
>      version, on could (I suppose) do
>          \ifthisisthescreenversion
>          \page
>          \fi
>          ... command to start Section 2.11 ...
>      but just putting
>          \testpage[5] % or whatever number one likes
>          ... command to start Section 2.11 ...
>      takes care of both formats.


1. You can add \testpage to the argument of the before key.

2. You can use modes for settings which apply for screen (or print) only.

\startmode[screen]
\setuphead[section][before={\testpage[4]\blank[...]}]
\stopmode

Wolfgang

___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________

[NTG-context] Re: *Not* starting a section at the very bottom of a page

[Jim]

On Thu, Apr 24, 2025 at 18:26 (+0200), Wolfgang Schuster wrote:

> Am 24.04.2025 um 18:04 schrieb Jim:
>> Aditya,

>> thanks for the fast reply.

>> On Thu, Apr 24, 2025 at 17:08 (+0200), Hans Hagen wrote:

>>> On 4/24/2025 5:00 PM, Jim wrote:
>>> > This could be a bug report, but it is mostly a request for assistance.

>>> > In
>>> > https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf
>>> > I see "2.11 Big operators" is at the very bottom of a page (no "content" of
>>> > section 2.11 is on that page).  This is an example of what I don't want,
>>> > and anyone who feels the same way would consider this a (very minor) bug
>>> > report for the (otherwise most excellent) math manual.

<snip>

>>> > Q: is there a ConTeXt macro which does a \page if there is less space on
>>> > the current page than specified by the argument to the macro?

>>> \testpage[3] % lines or some dimension

>>> It's typically something you only do when the document is final.

>> Hans,

>> thanks for the almost-as-fast-as-Aditya reply.

>> I am a bit puzzled by your "It's typically..." comment, for two reasons.
>> (1) When the document is (almost) final, I could just get out the "\page"
>> sledgehammer and whack away with that.
>> (2) The "bad" page break for Section 2.11 only occurs (at present) in the
>>      "screen" version, but not in the "paper" version.  To fix the screen
>> version, on could (I suppose) do
>>          \ifthisisthescreenversion
>>          \page
>>          \fi
>>          ... command to start Section 2.11 ...
>> but just putting
>>          \testpage[5] % or whatever number one likes
>>          ... command to start Section 2.11 ...
>> takes care of both formats.


> 1. You can add \testpage to the argument of the before key.

> 2. You can use modes for settings which apply for screen (or print) only.

> \startmode[screen]
> \setuphead[section][before={\testpage[4]\blank[...]}]
> \stopmode

Wolfgang,

thanks very much for that information... I need to make more use of before
(and after) in various places.

                                Jim
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / https://mailman.ntg.nl/mailman3/lists/ntg-context.ntg.nl
webpage  : https://www.pragma-ade.nl / https://context.aanhet.net (mirror)
archive  : https://github.com/contextgarden/context
wiki     : https://wiki.contextgarden.net
___________________________________________________________________________________