assignments.md

Assignments

This table illustrates which types can be assigned to each other.

Each cell shows if the assignment typeA = typeB is valid.

## Assignments with strict options:

typeB ➡️ typeA ⬇️	true	false	boolean	123	number	"foo"	string	undefined	null	111n	BigInt	never	void	any	unknown	{}
true	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
false	❌	✅	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
boolean	✅	✅	✅	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
123	❌	❌	❌	✅	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
number	❌	❌	❌	✅	✅	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
"foo"	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌	❌	✅	❌	✅	❌	❌
string	❌	❌	❌	❌	❌	✅	✅	❌	❌	❌	❌	✅	❌	✅	❌	❌
undefined	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	✅	❌	✅	❌	❌
null	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	✅	❌	✅	❌	❌
111n	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	✅	❌	✅	❌	❌
BigInt	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	✅	✅	❌	✅	❌	❌
never	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌
void	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	✅	✅	✅	❌	❌
any	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅
unknown	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅
{}	✅	✅	✅	✅	✅	✅	✅	❌	❌	✅	✅	✅	❌	✅	❌	✅

## Assignments with non-strict options:

typeB ➡️ typeA ⬇️	true	false	boolean	123	number	"foo"	string	undefined	null	111n	BigInt	never	void	any	unknown	{}
true	✅	❌	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
false	❌	✅	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
boolean	✅	✅	✅	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
123	❌	❌	❌	✅	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
number	❌	❌	❌	✅	✅	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
"foo"	❌	❌	❌	❌	❌	✅	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
string	❌	❌	❌	❌	❌	✅	✅	✅	✅	❌	❌	✅	❌	✅	❌	❌
undefined	❌	❌	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
null	❌	❌	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	❌	✅	❌	❌
111n	❌	❌	❌	❌	❌	❌	❌	✅	✅	✅	❌	✅	❌	✅	❌	❌
BigInt	❌	❌	❌	❌	❌	❌	❌	✅	✅	✅	✅	✅	❌	✅	❌	❌
never	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	❌	✅	❌	❌	❌	❌
void	❌	❌	❌	❌	❌	❌	❌	✅	✅	❌	❌	✅	✅	✅	❌	❌
any	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅
unknown	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅
{}	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	✅	❌	✅	❌	✅