Ah that’s good to know about zsh.

Sorry regarding the second code block; it does indeed work as intended, and quite elegantly.

For the first code snippet to run correctly, $list would need to be put in double quotes: echo "$list" | ... , because otherwise echo will conflate the various lines into a single line.

The for loop approach is indeed quite readable. To make it solve the original task (which here means that it should also assign a number just smaller than $threshold to $tail, if $threshold is not itself contained in $list), one will have to do something in the spirit of what @Ephera@lemmy.ml and I describe in these comments.

Thank you, in fact I ended up doing something that’s mathematically pretty much just that: I have the previous line stored in an auxiliary variable lastline, and it is the evaluation of the current line $0 that determines whether the previous line gets printed.

awk -v threshold=150 'BEGIN {lastline=""}
  (lastline!="" && threshold<$0){print lastline} #the additional check lastline!="" prevents an empty line at the very beginning
  {lastline=$0}
  END{print} #hardcode printing of the very last line, because otherwise it would never be printed
' 

Of note, in the case where some list entries are repeated, the behavior of this script will be:

• The threshold value, if it’s in the list, will always be printed just once, even if it occurs multiple times in the list, and also if it happens to be the first, last, or only entry in the list.
• All larger entries will be printed exactly as often as they occur in the list. This even holds for the largest value: its last repetition will be printed via the final END{print} statement, whereas all preceding instances get printed through the statement that depends on threshold<$0.

(IIRC, it was a StackOverflow post that led me to this.)