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Work in progress compiling logic

Posted On 05.19.2022

Started working on compiling logic, at this point, the compiler is capable of generating the opcode for the print, let statement and some arithmetic operators.

Since I don’t control the parsing flow (using generated code, thanks PeggyJS), I’m gonna handle the constant values (like numbers or strings) during the compilation process. The idea is, whenever we see a constant, we push it to the constant table and get the address of that value to use in the generated code.

So, for example, with a let statement, the generated code would be like this:

(let a 10)

After this, the constant table would contains one value, it look like this:

value index
10 1

For storing variables, I’ll just generate the opcode as STORE_NAME <name> for now. The right way to do this is to create another Symbol table, that handle the binding between the variable name and the constant value location. That’s for the next commit.

Also, I realized I made it this far but forgot to write a proper unit tests :( so had to stop and setup some tests. Jest is my test runner of choice, and set it up with ESBuild and TypeScript support seems to be a piece of cake.

The console.table method is pretty handful to debug tabular data like arrays or simple objects.

See commit 1405c28.