Well, this actually IS a valid "simple table".  So how is
pandoc to know that you intended it as a YAML metadata block?
Pandoc tries first to parse things as YAML blocks, and then as
tables, if either works, the parse succeeds with no error.

William Lupton <wlupton-QSt+ys/nuMyEUIsrzH9SikB+6BGkLq7r@public.gmane.org> writes:

> Should I expect syntax errors in YAML blocks to be detected and reported?
>
> This has a syntax error in the YAML block:
>
> % cat bad.md
> ---
> history:
> - number: Release 1.2
>   changes: |
>   - TBD
> ---
>
> This fixes it:
>
> % diff bad.md good.md
> 5c5
> <   - TBD
> ---
>>     - TBD
>
> The latest pandoc:
>
> % ~/Downloads/pandoc-2.14.0.1/bin/pandoc -v
> pandoc 2.14.0.1
> ...
>
> Pandoc thinks the bad YAML is a table:
>
> % ~/Downloads/pandoc-2.14.0.1/bin/pandoc bad.md
> <table>
> <tbody>
> <tr class="odd">
> <td>history:</td>
> </tr>
> <tr class="even">
> <td>- number: Release 1.2</td>
> </tr>
> <tr class="odd">
> <td>changes: |</td>
> </tr>
> <tr class="even">
> <td>- TBD</td>
> </tr>
> </tbody>
> </table>
>
> But it's OK with the good YAML:
>
> % ~/Downloads/pandoc-2.14.0.1/bin/pandoc good.md
>
> Parsing the file as YAML reports the error:
>
> % ~/Downloads/pandoc-2.14.0.1/bin/pandoc --metadata-file bad.md
> Error at "bad.md" (line 5, column 0):
> Unexpected ' '
>
> % ~/Downloads/pandoc-2.14.0.1/bin/pandoc --metadata-file good.md
> ^C
>
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