I'm working on some scripts where I want to remove every element from a
table in a single shot. In awk, "delete tbl" would do the trick, but Zeek
restricts delete operations to removing single elements. Worse, if I try
iterating over an aggregate to remove elements piece-wise, it doesn't
remove all of them, no doubt because the internal hash table is changing
mid-stream of the "for" loop and thus doesn't visit all of the members.
This means I have to first build up a *separate* vector of all the indexes,
then iterate over that to remove them.
Proposal: extend "delete" so that if applied to a table or a set, it clears
out all of its elements.
This seems straightforward to me, and something that I'll see if I can
find some cycles soon to hack out.
To satisfy my curiosity and to provide further info for anyone viewing list archives, I benchmarked assigning a new table() vs. running clear_table() on tables of various sizes & complexities. Assigning a new table() was clearly the winner by a huge margin.
It should be noted that these two methods are not completely equivalent. I run a script where a current table is periodically moved to an old table, and the current table cleared for further use. So, with A & B being tables of the same type:
B = A;
A = table();
works as intended, as B now contains the prior contents of A, and A is a new empty table.
B = A;
clears both, as they both point to the same table.