I've noticed in Angular 6 / Typescript code examples that fat arrow functions are used with two different syntaxes. Is there any distinction between them, or do they perform the same functionally?
blah.then(param => {
// perform some action with param
});
blah.then((param) => {
// execute some action with param
});
When it comes to JavaScript, there is no need for wrapping parentheses when there is only one argument in a fat-arrow function. They are treated as identical in this context.
foo => foo // this is acceptable
(foo) => foo // this is also acceptable
However, with TypeScript, the rules are slightly different. Even with a single argument, you still need to use parentheses to define a type for the parameter:
(foo: string) => foo // this is valid
foo: string => foo // this will result in a syntax error
It's important to note that this distinction is specific to JavaScript and TypeScript, and not related to Angular.
Furthermore, the concept of "fat arrow functions called" mentioned in your query actually refers to function expression rather than function invocation, as demonstrated in the examples you provided.
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