I have to admit that, whilst I am not convinced that these are the way to go for Excel (most Excel users don't want to 'program' Excel, and most 'useful' Lambda functions that I see are pretty complex, and I find that I struggle to understand Lambda functions that I wrote when I revisit them), I am using them an awful amount in my own workbooks.
One thing I especially like to do with Let formulae is to declare my variables up top, rather than in the body of the function. In a very simple example, rather than
=LET(res, FILTER($A$1:$A$500, $B$1:$B$500="Transfer"),
res)
I would write
=LET(method, "Transfer",
res, FILTER($A$1:$A$500, $B$1:$B$500=method),
res)
One issue I have come up against though is that I don't see to be able to setup a table variable in this way. Take this example formula
=LET(tx, tblTransactions,
method, "Transfer",
tx_date, TODAY(),
res, FILTER(tx[Date], (tx[Method]=method)*(tx[Date]>=tx_date)),
res)
I could use INDIRECT for the table, but I don't want to do that.
I could also define each of the table columns separately and reference those, but I was wanting to have a single point defining the table.
Does anyone else have this issue? Has anyone cracked it.