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* Lua filter documentation errors?
@ 2019-10-24 19:35 ChrisD
       [not found] ` <193ee2fd-7b82-6176-5cfd-353353816019-4SSc53hpTiu9TMao6EloiEEOCMrvLtNR@public.gmane.org>
  0 siblings, 1 reply; 2+ messages in thread
From: ChrisD @ 2019-10-24 19:35 UTC (permalink / raw)
  To: pandoc-discuss-/JYPxA39Uh5TLH3MbocFFw

I have been playing with lua filters, and I have a few corrections to the lua-filters page in the documentation. Nothing urgent, just figured I would pass these along...

1) The example for mediabag.fetch (https://pandoc.org/lua-filters.html#mediabag-fetch) is incorrect. Fetch returns two values. The second line should read:

     local mt, contents = pandoc.mediabag.fetch(diagram_url, ".")

2) In the mediabag list example usage (https://pandoc.org/lua-filters.html#mediabag-list), the for statement is incorrect. It needs a "do", and the colon should be removed.

3) The docs on mediabag (https://pandoc.org/lua-filters.html#module-pandoc.mediabag) say that "The media bag is used when pandoc is called with the --extract-media or --standalone option."

The media bag appears to be populated only when --extract-media is used, and not if --standalone is used without --extract-media.

4) The example for replacing placeholders with metadata values (https://pandoc.org/lua-filters.html#replacing-placeholders-with-their-metadata-value) fails if the metadata includes boolean values.

For example, if your YAML includes a line such as:
     toc: true

The code will fail with the error "attempt to index a boolean value". That's because boolean values are stored in the metadata table as MetaBools, which are lua booleans, not tables, and the "v.t" will fail. I believe this code will also fail if the metadata table contained a MetaString, though I do not know how to get a MetaString into the meta table; strings seem to be represented as MetaInlines. The code should check for MetaBools and MetaStrings, or check that (type(v) == "table").






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^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: Lua filter documentation errors?
       [not found] ` <193ee2fd-7b82-6176-5cfd-353353816019-4SSc53hpTiu9TMao6EloiEEOCMrvLtNR@public.gmane.org>
@ 2019-10-25  5:18   ` John MacFarlane
  0 siblings, 0 replies; 2+ messages in thread
From: John MacFarlane @ 2019-10-25  5:18 UTC (permalink / raw)
  To: ChrisD, pandoc-discuss-/JYPxA39Uh5TLH3MbocFFw


Thanks a lot.  I've added an issue on the tracker:
https://github.com/jgm/pandoc/issues/5851

ChrisD <cd34-gg-4SSc53hpTiu9TMao6EloiEEOCMrvLtNR@public.gmane.org> writes:

> I have been playing with lua filters, and I have a few corrections to the lua-filters page in the documentation. Nothing urgent, just figured I would pass these along...
>
> 1) The example for mediabag.fetch (https://pandoc.org/lua-filters.html#mediabag-fetch) is incorrect. Fetch returns two values. The second line should read:
>
>      local mt, contents = pandoc.mediabag.fetch(diagram_url, ".")
>
> 2) In the mediabag list example usage (https://pandoc.org/lua-filters.html#mediabag-list), the for statement is incorrect. It needs a "do", and the colon should be removed.
>
> 3) The docs on mediabag (https://pandoc.org/lua-filters.html#module-pandoc.mediabag) say that "The media bag is used when pandoc is called with the --extract-media or --standalone option."
>
> The media bag appears to be populated only when --extract-media is used, and not if --standalone is used without --extract-media.
>
> 4) The example for replacing placeholders with metadata values (https://pandoc.org/lua-filters.html#replacing-placeholders-with-their-metadata-value) fails if the metadata includes boolean values.
>
> For example, if your YAML includes a line such as:
>      toc: true
>
> The code will fail with the error "attempt to index a boolean value". That's because boolean values are stored in the metadata table as MetaBools, which are lua booleans, not tables, and the "v.t" will fail. I believe this code will also fail if the metadata table contained a MetaString, though I do not know how to get a MetaString into the meta table; strings seem to be represented as MetaInlines. The code should check for MetaBools and MetaStrings, or check that (type(v) == "table").
>
>
>
>
>
>
> -- 
> You received this message because you are subscribed to the Google Groups "pandoc-discuss" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to pandoc-discuss+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
> To view this discussion on the web visit https://groups.google.com/d/msgid/pandoc-discuss/193ee2fd-7b82-6176-5cfd-353353816019%40intielectronics.com.

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2019-10-24 19:35 Lua filter documentation errors? ChrisD
     [not found] ` <193ee2fd-7b82-6176-5cfd-353353816019-4SSc53hpTiu9TMao6EloiEEOCMrvLtNR@public.gmane.org>
2019-10-25  5:18   ` John MacFarlane

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