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Improve documentation of repl mod

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This commit is contained in:
Yann Hamdaoui 2021-01-19 11:07:35 +01:00
parent 5b0d6449f6
commit 26371984c1
1 changed files with 12 additions and 7 deletions
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19
src/repl.rs
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@ -21,8 +21,11 @@ use std::str::FromStr;
generate_counter!(InputNameCounter, usize);
/// Result of the evaluation of an input.
pub enum EvalResult {
/// The input has been evaluated to a term.
Evaluated(Term),
/// The input was a toplevel let, which has been bound in the environment.
Bound(Ident),
}
@ -34,11 +37,11 @@ impl From<Term> for EvalResult {
/// Interface of the REPL backend.
pub trait REPL {
/// Eval an expression.
/// Evaluate an expression, which can be either a standard term or a toplevel let-binding.
fn eval(&mut self, exp: &str) -> Result<EvalResult, Error>;
/// Load the content of a file in the environment. Return the loaded record.
fn load(&mut self, path: impl AsRef<OsStr>) -> Result<RichTerm, Error>;
/// Typecheck an expression and return the apparent type.
/// Typecheck an expression and return its [apparent type](../typecheck/fn.apparent_type.html).
fn typecheck(&mut self, exp: &str) -> Result<Types, Error>;
/// Query the metadata of an expression.
fn query(&mut self, exp: &str) -> Result<Term, Error>;
@ -50,14 +53,14 @@ pub trait REPL {
pub struct REPLImpl {
/// The underlying cache, storing input, loaded files and parsed terms.
cache: Cache,
/// The parser.
/// The parser, supporting toplevel let declaration.
parser: ExtendedParser,
/// The eval environment. Contain the global environment with the stdlib, plus declarations and
/// loadings made inside the REPL.
/// The eval environment. Contain the global environment with the stdlib, plus toplevel
/// declarations and loadings made inside the REPL.
eval_env: eval::Environment,
/// The typing environment, counterpart of the eval environment for typechecking. Entries are
/// `TypeWrapper` for the ease of interacting with the typechecker, but there are not any
/// unification variable in it.
/// [`TypeWrapper`](../typecheck/enum.TypeWrapper.html) for the ease of interacting with the
/// typechecker, but there are not any unification variable in it.
type_env: typecheck::Environment,
}
@ -189,6 +192,7 @@ pub mod command {
pub struct UnknownCommandError {}
/// Check that an argument is non-empty, or return an error with the given optional message.
fn require_arg(cmd: CommandType, arg: &str, msg_opt: Option<&str>) -> Result<(), REPLError> {
if arg.trim().is_empty() {
Err(REPLError::MissingArg {
@ -218,6 +222,7 @@ pub mod command {
}
impl CommandType {
/// Return the aliases of a command.
pub fn aliases(&self) -> Vec<String> {
use CommandType::*;