convert-a-string-to-a-number

Convert a String to a Number!

Note: This kata is inspired by Convert a Number to a String!. Try that one too.

Description

We need a function that can transform a string into a number. What ways of achieving this do you know?

Note: Don't worry, all inputs will be strings, and every string is a perfectly valid representation of an integral number.

Examples

stringToNumber("1234") == 1234
stringToNumber("605" ) == 605
stringToNumber("1405") == 1405
stringToNumber("-7"  ) == -7