Forty Languages Is Not Forty Grammars

People assume language support is a parser problem. Parsing is the first afternoon. The three weeks go somewhere else.

Conventions

Every language has a house style that no specification records: where the error goes, how a constructor is named, whether a helper is private by underscore or by module. A completion that ignores it is correct and still wrong.

The standard library

Knowing a language means knowing what you do not have to write. Most of the work is teaching the index which standard functions exist, what they cost, and which of the three obvious ways to do a thing the community settled on.

The evaluation set

A language is not supported until it has its own tasks in the evaluation set, written by somebody who uses it daily. That is the part we refuse to rush, and it is why the count goes up slowly.