Re: question about parameter expansion

[Ray Andrews <rayandrews@eastlink.ca>]

On 09/26/2015 02:34 PM, Bart Schaefer wrote:
> On Sep 26,  2:11pm, Ray Andrews wrote:
> }
> } Where is this sort of thing discussed in the manual?
>
> Under "Parameter Expansion".

Ooops ... My eye caught 'parameters, expanding', but  see there is indeed
'parameter expansion' as well.  That's a bit lazy of me.
>
> Perhaps unfortunately, you need to get familar with shell language
> terminology.
Yes.
> The strings $1, $2, etc. are referred to as "positional
> parameters" whereas $a, $foo, $PATH, etc. are "named parameters".
> The signifier "$" is said to introduce an expansion.  (It used to
> be that it only introduced a parameter expansion, and parts of the
> doc still talk about it that way, but now it also introduces other
> expansions like command substitution and arithmetic.)
>
> The word "variable" is usually a synonym for "named parameter," but
> might also refer to named strings in the process environment, which
> can be referenced as if they were named parameters.

Without exaggeration that's the most useful minute of reading I've done 
as to
zsh so far.  If I'd read that two years ago it would have saved me hours 
of grief.

>
> } In any case looking for 'parameter expansion' in the index is no help.
>
> This is a thing about the yodl/info documentation model that I don't
> like.  I think all the (sub)section headings should be in the index.
> Instead the section headings are in "menus" (which don't show up at all
> in the manpage-formatted documentation) and you can't find them with an
> index search.

When all else fails, an excellent index comes to the rescue.  An 
excellent glossary
is as valuable.

>
> In this specific case, though, "parameter expansion" does appear in the
> index, along with "parameter expansion flags", "parameter modifiers",
> etc.  How were you searching the index?
>
> } 'Variable' doesn't exist in the index at all
>
> ??
>
> * variables:                             Parameters.         (line    6)
> * variables, environment:                Parameters.         (line   25)
>
> Again, exactly how are you searching what index?  Have you tried always
> searching case-insensitively?

U
     umask    17. Shell Builtin Commands
     Unicode combining characters    16.2.12 Zle
     unset parameters, substituting    16.2.3 Expansion and Globbing
     until loops    6.3 Complex Commands
     user contributions    26. User Contributions
     user selection    6.3 Complex Commands
     users, watching    17. Shell Builtin Commands

V
     version                                    The Z Shell Manual
     version control utility            26.4 Gathering information from 
version control systems

W
     waiting before rm *

... pardon the busted formatting, but that's the Index as I see it. Am I 
barking up the
wrong tree somehow?