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the_sleaze_ 19 days ago | parent | context | favorite | on: The intricacies of implementing memoization in Rub...

I use this to memoize instance vars from time to time, whenever nil could be considered valid

    return x if defined? x

    x = ingest_stock_market

`defined?` won't evaluate the parameter either which is nice whereas things like blank? present? and presence do

JadeNB 19 days ago [–]

> return x if defined? x

It's a natural pattern, and translates with obvious changes to Perl, but still `x = defined? x ? x : y` is longer than `x //= y`, so all I was meaning to say in my original comment was that I was surprised that Ruby didn't borrow the latter from Perl.

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