Write a function called concatStrings that takes in two strings as arguments and returns the two strings joined together with a space between. Write a function called firstLetter that takes in a ...

If you find writing type definitions in comments in your files too noisy, you can choose to write those definitions in a declaration file instead. TypeScript declaration files are the .d.ts files ...

Spending some time with running + writing JavaScript tests. Write tests for the following, and then make the tests pass! A capitalize function that takes a string and returns it with the first ...