in this nodejs code,
declare var process: NodeJS.Process;
declare var global: NodeJS.Global;
declare var console: Console;
declare var __filename: string;
declare var __dirname: string;
that...
What's the difference between 'declare var' and 'var'?
When I look up on the googling, I get the word runtime.
wiki says runtime is an operation while a computer program is running....
but i can't understand.
and line 1, what does it mean by ":" after "process" and then "NodeJS.Process"?
Is that mean "process" is equal "NodeJS.Process"?
also line 4, what does it mean by ":" after "__filename" and then "string"?
Is that mean "__filename" is equal "string"?
thanks you.
1 Answer
When you use:
var process: NodeJS.Process;
You are creating a variable named process (with no value defined) and telling the TypeScript compiler to enforce the NodeJS.Process type for assignments.
When you add declare:
declare var process: NodeJS.Process;
You are telling the TypeScript compiler that there is already a variable named process with the type NodeJS.Process. This is useful when you have variables introduced by sources that the compiler is not be aware of.
