Re: compound commands with subshells/braces

[Eric Blake <ebb9@xxxxxxx>]

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According to Geoff Clare on 5/27/2009 3:52 AM:
>     complete_command : list non_empty_separator
>                      | list END_OF_INPUT
>                      ;
> 
> (with an explanation somewhere of what END_OF_INPUT means: either
> end of file, the end of a -c option-argument, the end of the text
> inside $(...) or `...`, or the end of the arguments to an eval
> command).

Traditional shells also treated end of file as a valid here-doc
terminator, so that part of the grammar would also need some touch-ups to
make it clear whether this is well-defined or a syntax error:

sh -c 'cat <<EOF
hi'

Also, you need to make sure the definition of the END_OF_INPUT avoids
creating ambiguous situations with $() substitutions interacting with
here-docs.  It would be worth having the standard specify whether both of
these examples are well-behaved (and print hi) or syntax errors:

echo $(
cat <<\)
hi
)
)

echo $(
cat <<EOF
hi
EOF)

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9@byu.net
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