The near-complete obviation of nulls is perhaps the most frequently- (and hilariously-) cited benefit of working in F#, as compared to C#. Nulls certainly still exist in F#, but as a practical matter it really is quite rare that they need to be considered explicitly within an all-F# codebase. It turns out this cuts both ways. On those infrequent occasions where one does need to check for nulls, F# actually makes it surprisingly difficult to do so safely and efficiently. In this post I’ve tried to aggre[...]

The Problem “Motif finding is a problem of finding common substrings of specified length in a set of strings. In bioinformatics, this is useful for finding transcription binding sites” (recap here). The problem is succinctly stated on Rosalind. Given a set of strings DNA of size t, find “most common” substrings of length k. “Most common” means, that substrings […]

Working on the command line with Powershell, much of the time I have the luxury of dealing directly with rich .NET objects.  If I need to sort, filter, or otherwise process cmdlet output, I have easy access to typed properties and methods right at the prompt. Often, though, I'll need to wrangle plain text, perhaps … Continue reading A handy Powershell filter for converting plain text to objects →

Working on the command line with Powershell, much of the time I have the luxury of dealing directly with rich .NET objects.  If I need to sort, filter, or otherwise process cmdlet output, I have easy access to typed properties and methods right at the prompt. Often, though, I’ll need to wrangle plain text, perhaps from a log file or the output of an executable.  In these cases an intermediate step is required in order to extract the typed information (timestamps, substrings, numerical fields, etc) from th[...]

As much as we people who write code like to talk about code, the biggest challenge in a software project is not code. A project rarely fails because of technology – it usually fails because of miscommunications: the code that is delivered solves a problem (sometimes), but not the right one. One of the reasons we often deliver the wrong solution is that coding involves translating the world of the original problem into a different language. Translating one way is hard enough as it is, but then, rarely are u[...]