Re: Scheme: get current beam-thickness

[David Kastrup]

Aaron Hill <address@hidden> writes:

> On 2020-01-25 12:05 pm, David Kastrup wrote:
>> Aaron Hill <address@hidden> writes:
>> 
>>> On 2020-01-25 11:40 am, David Kastrup wrote:
>>>> Aaron Hill <address@hidden> writes:
>>>>> I am unaware of any simpler approach, as it is my understanding that
>>>>> grobs do not persist the entire context within which they were
>>>>> created.
>>>> How would they then make it to the page?  Suicided grobs have their
>>>> properties deleted prematurely, but those are not the rule.
>>>> 
>>>>> Mind you, I would love to be shown that I am incorrect.
>>>> This is Scheme anyway.  In general, objects persist as long as you
>>>> are
>>>> able to reference them.
>>> Wait, do grobs have a reference to the context?
>> No, or this would cause the contexts to persist until the end of 
>> typesetting.
>> 
>>> I know you can use \applyOutput to process grobs at a given moment in
>>> time, and that provides you access to both the grobs and the context.
>>> And my snippet showed using an engraver to achieve something similar.
>>> But within, say, a stencil procedure, it seems like you only have the
>>> grob to work with.  Is there some ly:grob-context method that I have
>>> been overlooking?
>> You wrote "it is my understanding that grobs do not persist the
>> entire
>> context within which they were created".  "persist" is an intransitive
>> verb, so your statement was about the duration of grobs, not of
>> contexts.
>
> Wiktionary disagrees.  The fourth definition is computing-specific and
> allows "persist" to be transitive: "to *cause* to be persisted, made 
> permanent" (emphasis mine).
>
> But who cares what some crowd-sourced site says.

dak@lola:/usr/local/tmp/lilypond$ dict persist
3 definitions found

>From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Persist \Per*sist"\, v. i. [imp. & p. p. {Persisted}; p. pr. &
     vb. n. {Persisting}.] [L. persistere; per + sistere to stand
     or be fixed, fr. stare to stand: cf. F. persister. See
     {Per-}, and {Stand}.]
     To stand firm; to be fixed and unmoved; to stay; to continue
     steadfastly; especially, to continue fixed in a course of
     conduct against opposing motives; to persevere; -- sometimes
     conveying an unfavorable notion, as of doggedness or
     obstinacy.
     [1913 Webster]
  
           If they persist in pointing their batteries against
           particular persons, no laws of war forbid the making
           reprisals.                               --Addison.
     [1913 Webster]
  
           Some positive, persisting fops we know,
           Who, if once wrong, will needs be always so. --Pope.
     [1913 Webster]
  
           That face persists.
           It floats up; it turns over in my mind.  --Mrs.
                                                    Browning.
     [1913 Webster]
  
     Syn: See {Persevere}, and {Insist}.
          [1913 Webster] Persistence

>From WordNet (r) 3.0 (2006) [wn]:

  persist
      v 1: continue to exist; "These stories die hard"; "The legend of
           Elvis endures" [syn: {prevail}, {persist}, {die hard},
           {run}, {endure}]
      2: be persistent, refuse to stop; "he persisted to call me every
         night"; "The child persisted and kept asking questions" [syn:
         {persevere}, {persist}, {hang in}, {hang on}, {hold on}]
      3: stay behind; "The smell stayed in the room"; "The hostility
         remained long after they made up" [syn: {persist}, {remain},
         {stay}]

(3rd source is just a thesauraus).

> If you prefer "persist" only to be intransitive, then we need another
> verb or phrasing.  How about: "Grobs do not maintain their own copy
> nor reference to the context in which they were created."  Is that an
> accurate statement?

Yes.  You could also just replace your transitive "persist" with "make
persist" or "cause to persist" and turn it into proper English.  If you
want to use your 4th meaning, I'd strongly recommend using it only in
constructs where it cannot possibly be one of the other meanings.

-- 
David Kastrup