Small IR docs, and then some learning about rustdoc.

src/backend.rs

@@ -1,4 +1,4 @@
-//! # The compiler backend!
+//! # The compiler backend: generation of machine code, both static and JIT.
 //! 
 //! This module is responsible for taking our intermediate representation from
 //! [`crate::ir`] and turning it into Cranelift and then into object code that
@@ -15,19 +15,16 @@
 //! they share a lot of behaviors. However, you'll want to use different variants
 //! based on your goals:
 //! 
-//!   * Use `Backend<ObjectModule>`, constructed via
-//!     [`Backend::object_file`](self::backend::Backend::object_file), if you
-//!     want to compile to an object file on disk, which you're then going to
-//!     link to later.
-//!   * Use `Backend<JITModule>`, constructed via
-//!     [`Backend::jit`](self::backend::Backend::jit), if you want to do
-//!     just-in-time compilation and are just going to run things immediately.
+//!   * Use `Backend<ObjectModule>`, constructed via [`Backend::object_file`],
+//!     if you want to compile to an object file on disk, which you're then going
+//!     to link to later.
+//!   * Use `Backend<JITModule>`, constructed via [`Backend::jit`], if you want
+//!     to do just-in-time compilation and are just going to run things immediately.
 //! 
 //! ## Working with Runtime Functions
 //! 
 //! For now, runtime functions are pretty easy to describe, because there's
-//! only one. In the future, though, the
-//! [`RuntimeFunctions`](self::backend::RuntimeFunctions) object is there to
+//! only one. In the future, though, the [`RuntimeFunctions`] object is there to
 //! help provide a clean interface to them all.
 mod error;
 mod eval;

src/eval.rs

@@ -1,3 +1,4 @@
+//! Helpful functions for evaluating NGR programs.
 mod env;
 mod primop;
 mod value;

src/ir.rs

@@ -1,3 +1,17 @@
+//! The middle of the compiler: analysis, simplification, optimization.
+//! 
+//! For the moment, this module doesn't do much besides define an intermediate
+//! representation for NGR programs that is a little easier to work with then
+//! the structures we've built from the actual user syntax. For example, in the
+//! IR syntax, function calls are simplified so that all their arguments are
+//! either variables or constants, which can make reasoning about programs
+//! (and implicit temporary variables) quite a bit easier.
+//! 
+//! For the foreseeable future, this module will likely remain mostly empty
+//! besides definitions, as we'll likely want to focus on just processing /
+//! validating syntax, and then figuring out how to turn it into Cranelift
+//! and object code. After that point, however, this will be the module to
+//! come to for analysis and optimization work.
 mod ast;
 mod eval;
 mod from_syntax;

src/ir/from_syntax.rs

@@ -1,7 +1,7 @@
 use internment::ArcIntern;
 
 use crate::ir::ast as ir;
-use crate::syntax::ast as syntax;
+use crate::syntax as syntax;
 
 impl From<syntax::Program> for ir::Program {
     fn from(mut value: syntax::Program) -> Self {

src/lib.rs

@@ -61,18 +61,14 @@
 //! for evaluating all expressions. The [`eval`] module provides some
 //! utility support for this work.
 //! 
-/// The front-end of the compiler: lexing, parsing, validation
 pub mod syntax;
-/// The middle of the compiler: analysis, simplification, optimization
 pub mod ir;
-/// The backend of the compiler: transformation to Cranelift, runtime
 pub mod backend;
-/// Helpful functions for evaluating NGR programs
 pub mod eval;
 
-/// Implementation module for the high-level compiler
+/// Implementation module for the high-level compiler.
 mod compiler;
-/// Implementation module for the high-level REPL
+/// Implementation module for the high-level REPL.
 mod repl;
 
 pub use crate::compiler::Compiler;

src/syntax.rs

@@ -1,20 +1,47 @@
+//! NGR Parsing: Reading input, turning it into sense (or errors).
+//! 
+//! This module implement the front end of the compiler, which is responsible for
+//! reading in NGR syntax as a string, turning it into a series of reasonable Rust
+//! structures for us to manipulate, and doing some validation while it's at it.
+//! 
+//! The core flow for this work is:
+//! 
+//!   * Turning the string into a series of language-specific [`Token`]s.
+//!   * Taking those tokens, and computing a basic syntax tree from them,
+//!     using our [`parser`].
+//!   * Validating the tree we have parsed, using the [`validate`] module,
+//!     returning any warnings or errors we have found.
+//!   * Simplifying the tree we have parsed, using the [`simplify`] module,
+//!     into something that's more easily turned into our [compiler internal
+//!     representation](super::ir).
+//! 
+//! In addition to all of this, we make sure that the structures defined in this
+//! module are all:
+//!
+//!   * Instances of [`Pretty`](::pretty::Pretty), so that you can print stuff back
+//!     out that can be read by a human. 
+//!   * Instances of [`Arbitrary`](proptest::prelude::Arbitrary), so they can be
+//!     used in `proptest`-based property testing. There are built-in tests in
+//!     the library, for example, to make sure that the pretty-printing round-trips.
+//!   * Can be evaluated using an `eval` function, for comparison with later
+//!     versions of the function downstream.
 use codespan_reporting::{diagnostic::Diagnostic, files::SimpleFiles};
 use lalrpop_util::lalrpop_mod;
 use logos::Logos;
 
 mod arbitrary;
-pub mod ast;
+mod ast;
 mod eval;
 mod location;
-mod simplify;
+pub mod simplify;
 mod tokens;
 lalrpop_mod!(
     #[allow(clippy::just_underscores_and_digits, clippy::clone_on_copy)]
-    parser,
+    pub parser,
     "/syntax/parser.rs"
 );
 mod pretty;
-mod validate;
+pub mod validate;
 
 pub use crate::syntax::ast::*;
 pub use crate::syntax::location::Location;