tl_new, text_new return values owned by others

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kernel
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tl_new, text_new return values owned by others

Postby kernel » 08 Sep 2016

Hi,

I found that tl_new and text_new return values owned by others, as the consequence of that, tl_delete deletes the wrong object.

Normally, handles returned by some creation function are "random" numbers, not positive integers as in MC, to maintain its uniqueness and avoid the aforementioned conflict problem.

Any inputs? thanks.

-kernel
Last edited by kernel on 24 Sep 2016, edited 1 time in total.

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TJ
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Re: tl_new, tl_new return values owned by others

Postby TJ » 08 Sep 2016

Hi,

I found that tl_new and tl_new return values owned by others, as the consequence of that, tl_delete deletes the wrong object.

Normally, handles returned by some creation function are "random" numbers, not positive integers as in MC, to maintain its uniqueness and avoid the aforementioned conflict problem.

Any inputs? thanks.

-kernel

GIGO

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JoshM
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Re: tl_new, tl_new return values owned by others

Postby JoshM » 09 Sep 2016

I found that tl_new and tl_new return values owned by others, as the consequence of that, tl_delete deletes the wrong object.
(Just to check we're on the same page: you mention `TL_New()` and `TL_New()` here. Is your question about comparing two of the same keywords?)

When you get the trend line ID (like with `TL_GetNext()`), you can specify the drawing origin. With that you can have `TL_GetNext()` return only trend line IDs from trend lines owned by the current script (and thus prevent removing the wrong trend line). (If this is what you meant with "values owned by others".)

If I assume you're comparing `TL_New()` with another drawing keyword (like `Text_New()`), then both keywords can return the same numerical ID. But this is by design and documented. That is, `TL_New()` returns "a trendline-specific ID number"(and no "drawing-specific ID number").
Normally, handles returned by some creation function are "random" numbers, not positive integers as in MC, to maintain its uniqueness and avoid the aforementioned conflict problem.
Each text, trend line, or arrow drawing gets its own ID number. And so there is no conflict problem from the standpoint of PowerLanguage.

(There might be in your script, but that's then a conflict that probably should be coded around. Since PowerLanguage provides no native capabilities to iterate over a collection of drawings, features to distinguish between drawings of one type versus those of another are also missing.)

kernel
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Re: tl_new, text_new return values owned by others

Postby kernel » 24 Sep 2016

Josh,

Thanks for the reply. the 2nd one was meant to be "text_new"...a typo, sorry.


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