G'day gregory-nisbet,

"What's the idiomatic way to guard against unintentionally expanding a non-singleton list into the bodies of your hashes?"

I don't know if there's an idiom for that specific case; however, as a general case, you can use scalar to force scalar context. So, if you're happy to have undef values in your hash: 

key1 => scalar(some_key($bar))

[download]

If you don't want undef values and are using perl v5.10, or higher, you can do something like these: 

key1 => (some_key($bar) // 0)
key1 => (some_key($bar) // [])

[download]

If none of those suit, then what you're currently doing ("use an intermediate scalar variable") seems like a perfectly fine solution.

— Ken

In reply to Re: Preventing unintended list expansion inside hash literals. by kcott
in thread Preventing unintended list expansion inside hash literals. by gregory-nisbet

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