>From: aotto1968 <aotto1968@t-online.de>
>Date: Fri May 20 10:13:12 GMT 2022
>Subject: proposal: lmap is missing the stride option

>
>"lmap" is a new command to tcl able to filter lists BUT missing the
>feature to work an "stride" lists.
>
>a stride list is a list with a pattern of multiple items.
>example: The "array get…" produce a flat list of stride of "2"
>
>code: lmap {k v} $packageDEF {list $k [lindex $v 1]}

>the code above create a list of lists:
>
> > {k1 v11} {k2 v21} …
>
>but I want to have
>
> > k1 v11 k2 v22 …

[concat {*}[lmap {k v} $packageDEF {list $k [lindex $v 1]}]

will get the result you want.

I end up using this a lot, and would like a cleaner way to have the script argument to lmap generate multiple items in the lmap result.

However I do not think -stride is the proper name for this option, and do not see why a number of items is necessary or even useful. Why not just append as many items as appear in the script result treated as a list?

Perhaps adding a option (-concat ?) to lmap which concatenates the result of the script to the [lmap] result. Something like:

lmap -concat {k v} $packageDEF {list $k [lindex $v 1]}

Dave B