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Daniel Zaltsman
Daniel Zaltsman

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Difference between for...in and for...of

For...of

For...of loops are used to loop through the values of iterable objects:
-Arrays
-Strings
-Maps
-Sets
-Generators
-Dome node collections
-The arguments object

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For...in

For...in loops are used to loop over the properties of an object, such as object keys or array indexes.

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typescript

11 Tips That Make You a Better Typescript Programmer

1 Think in {Set}

Type is an everyday concept to programmers, but it’s surprisingly difficult to define it succinctly. I find it helpful to use Set as a conceptual model instead.

#2 Understand declared type and narrowed type

One extremely powerful typescript feature is automatic type narrowing based on control flow. This means a variable has two types associated with it at any specific point of code location: a declaration type and a narrowed type.

#3 Use discriminated union instead of optional fields

...

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