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Discussion on: Typescript can be confusing

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jonrandy profile image
Jon Randy 🎖️ • • Edited

Instead of parseInt

['1', '2', '10'].map(x=>~~+x)
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Works - and shorter

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tomaszs2 profile image
Tom Smykowski • • Edited

dev-to-uploads.s3.amazonaws.com/i/...

:)

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Calin Baenen •

The hell did I just read?

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peerreynders profile image
peerreynders • 
> ['1', '4294967295', '10'].map(x=>~~+x)
(3) [1, -1, 10]
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Bitwise NOT (~):

The operands are converted to 32-bit integers and expressed by a series of bits (zeroes and ones). Numbers with more than 32 bits get their most significant bits discarded.

Unsigned right shift (>>>):

Unlike the other bitwise operators, zero-fill right shift returns an unsigned 32-bit integer.

Know the limitations of your tools.

Integers and shift operators in JavaScript

> ['1.1', '9007199254740991.6', '10.9'].map(n => parseInt(n))
(3) [1, 9007199254740991, 10]
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jonrandy profile image
Jon Randy 🎖️ •

I know all that, but for the purposes of a simple string -> integer parser, this works just fine

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natelindev profile image
Nathaniel •

that works, but unreadable, therefore it's a bad practice, should be ['1', '2', '10'].map(n => Number.parseInt(n));