The ?? operator was added to TypeScript 3.7 back in November 2019. And more recently, the ?? operator was included in ES2020, which is supported by Node 14 (released in April 2020).

2017年1月17日 · Yes. As of TypeScript 3.7 (released on November 5, 2019), this feature is supported and is called Optional Chaining: At its core, optional chaining lets us write code …

2019年7月20日 · See TypeScript non-goal number 7: Introduce behaviour that is likely to surprise users. Instead have due consideration for patterns adopted by other commonly-used …

2017年2月16日 · That's the non-null assertion operator. It is a way to tell the compiler "this expression cannot be null or undefined here, so don't complain about the possibility of it being …

2019年6月10日 · I stumped on something in Typescript today. What does the three dots mean in this type? I can't find anything that explain this at all. I'm trying to do something like this let all: { …

2018年6月23日 · That is a "definite assignment assertion": varname !: sometype informs typescript not to worry about checking if varname might be unassigned (it tells typescript that …

2010年5月10日 · For those with experience with C#, the double-pipe operator is equivalent to null-coalesce operator ??. Javascript evaluates non-null objects like true (or better evalualtes null …

What is the TypeScript language? What can it do that JavaScript or available libraries cannot do, that would give me reason to consider it?

2022年1月27日 · The as keyword is a Type Assertion in TypeScript which tells the compiler to consider the object as another type than the type the compiler infers the object to be.

2015年11月5日 · Since the release of deno, you can now execute deno run path/to/file.ts and it will run typescript files in a single command without compiling it to a separate JS file.