Verifying leftPad() in Whiley

The leftPad(string,int) function simply pads a string up to a given size by inserted spaces at the beginning. For example, leftPad("hello",8) produces " hello". This little function shot to fame in 2016 when a developer pulled all his modules from NPM, of which one provided the leftPad() functionality.

Whiley Demo @ Oracle Labs!!

Recently, I gave a demo of Whiley at Oracle Labs in Brisbane which they have kindly put up on YouTube: The actual demo itself starts around 11:30s, so you might want to skip on to that.

Property Syntax in Whiley

Recently, I gave a demo which showed off thew new “Property Syntax” in Whiley. Whilst this is still in the devel branch it will make its way, soon enough, into the next release.

Understanding Effective Unions in Whiley

The concept of effective union types in Whiley exposes some interesting features worth considering. In particular, they result in a separation between the readable and writeable view of a type. But, we’re getting ahead of ourselves!

Program Specification in Practice?

Recently, as part of our Programming Languages Reading group, we looked at the paper “Contracts in Practice” by Estler et al., (see here for a copy). This is quite an interesting paper and the authors perform an empirical investigation as to how contracts are used by programmers in practice.