Re: How to disable certain completion tags?

[Martin Vaeth <martin@xxxxxxxx>]

Mikael Magnusson <mikachu@xxxxxxxxx> wrote:
> Martin Vaeth <martin@xxxxxxxx> wrote:
>>
>> zstyle ':completion:*:*:dummy:*' tag-order ''
>>
>> [...] does not show any effect.
>
> Does this help?
>
>               -      If any value consists of only a  hyphen [...]

Thanks for the reply. But this is not exactly what I intended:

zstyle ':completion:*:*:dummy:*' tag-order -

switches off completion completely for "dummy" (in particular, also
"dummy --f<tab>" is not being completed to "dummy --foo="); I only
want to switch off completion for the tag "foo" (in the example after
"dummy --foo=<tab>").
None of my alternative attempts like (actually I had tried many more)

zstyle ':completion:*:*:dummy:*' tag-order '- ! foo'
zstyle ':completion:*:*:dummy:*' tag-order - '!' foo
zstyle ':completion:*:*:dummy:*' tag-order - '!foo'
zstyle ':completion:*:*:dummy:*' tag-order '- !foo'
zstyle ':completion:*:*:dummy:*' tag-order '!foo'
zstyle ':completion:*:*:dummy:*' tag-order '!' foo

seems to have any effect, either.