Lately, I decided to delve into the world of TypeScript. I am intrigued by the fact that the following code snippet seems to work without any issues in this language:
function f(): boolean {
return false;
}
if ( f ) {
performSomeAction();
}
Despite what many programmers would consider a typo (missing call parentheses for the function) and likely rewrite it like this:
if( f() ){
performSomeAction();
}
Is there actually a practical reason for a function object to evaluate to true? Or is it simply a loophole that makes the code more susceptible to errors?
[SOLUTION] To prevent such mishaps, one can adjust their coding style. By using "===" for strict equality checks in conditional statements, the first example will result in a TypeScript compiler error stating: "Operator '===' cannot be applied to types '() => boolean' and 'boolean'".