Depends. Probably not significant unless it's really hot code (ex parser stap).
That likely wouldn't be a significant deal breaker, just worth considering.
My main counter is, why increase complexity, making the code both harder to read and maintain when defining entry using 'let' is much simpler/easier to understand.
To each their own. I bias heavily toward simple/maintainable code even of it's not 100% semantically perfect. Ie avoid adding complexity unless it's 100% necessary.
I think defining using a let is the harder to read and maintain option than my option, and going that path increases complexity TBH.
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