On 5/25/23 8:13 AM, Robert Elz wrote:
Note that ${C } is not a group - it is syntax that delimits a command
substituition in a word, and what's in a command substitution is a list
(which can contain groups, or be one, but isn't required to be).
There's not any real difference. A group command is
'{' compound_list '}',
a nofork command substitution is
'${' compound_list '}',
and a command substitution is
'$(' compound_list ')'.
(Similar to how a subshell command is
'(' compound_list ')' ).
This is consistent with the POSIX grammar. The difference, as you say, is
that a command substitution is allowed as part of a word, so the closing
brace isn't a reserved word according to the strict definition.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU [email protected] http://tiswww.cwru.edu/~chet/