In Lasso 9, does -recordindex parameter of field method exist? Alternatives?

Question

In old Lasso 8 code, I would frequently use field('foo', -recordindex=(loop_count - 1)) in a conditional to display a header row in a table when a value changed between records.

In Lasso 9, the -recordindex parameter seems to be ignored. It's also not documented.

My first workaround would be to set a variable with each record iteration and compare the current record's field against that value.

<?= var('lastSortFieldValue') = null ?>
[records]
    [if(field('sortField') != $lastSortFieldValue)]
        <!-- display header -->
    [/if]
    <!-- display row -->
    <?= $lastSortFieldValue = field('sortField') =>
[/records]

Any recommendations for a best practice here?

Answer 1

Your workaround of setting the variable is probably the best thing to do. (Though I would make it a local variable instead of a thread variable as it probably doesn't need to have thread scope.)

If you really wanted a method that would do what field(..., -recordIndex) used to do, then here's a method to do that:

define fieldFromRow(field::string, row::integer) => {
    local(curMap = inline_scopeGet)
    !#curMap || #curMap->size == 0? return null;

    local(stashRow) = #curMap->find(::currentrow)
    handle => {
        #curMap->insert(::currentrow = #stashRow)
    }

    #curMap->insert(::currentrow = #curMap->find(::currentset)->get(INLINE_RESULTROWS_POS)->get(#row))

    return column(#field)
}

This method gets the current inline information. Then it stashes the current row and sets a handler to restore the current row when all is said and done. It then sets the current row to the one specified in the method call and returns the value for the specified field. A bit of a hack, but it works in my basic testing.