Just a Number please

Number conversion: just a number please

Converting something to a Number can be a puzzling experience in ECMAScript (ES). There are edge cases with weird results. For example Number(null) or Number([]) return 0. Trying to convert a Symbol will throw a TypeError.

So here's a small utility (a factory function) to convert input to the numbers one expects. It returns NaN when conversion doesn't comply to our standards¹ (so: [nr utility](null) will return NaN).

Notes:

• most edge cases are mitigated, not all.
• Number strings containing ',' (e.g. 0.42.toLocaleString("nl"): '0,42') will also be converted.
• By default the function from the the factory does not include 'converting' Infinity (to ... well ... Infinity).

The embedded Stackblitz example compares the result of default (ES) conversion (Number(...)) to conversion using the utility for a number of values.

¹ Which may very well not be your standards, feel free to comment or modify the function

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