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-rw-r--r--users/glittershark/achilles/src/passes/hir/strip_positive_units.rs189
1 files changed, 0 insertions, 189 deletions
diff --git a/users/glittershark/achilles/src/passes/hir/strip_positive_units.rs b/users/glittershark/achilles/src/passes/hir/strip_positive_units.rs
deleted file mode 100644
index 91b56551c8..0000000000
--- a/users/glittershark/achilles/src/passes/hir/strip_positive_units.rs
+++ /dev/null
@@ -1,189 +0,0 @@
-use std::collections::HashMap;
-use std::mem;
-
-use ast::hir::Binding;
-use ast::Literal;
-use void::{ResultVoidExt, Void};
-
-use crate::ast::hir::{Decl, Expr};
-use crate::ast::{self, Ident};
-
-use super::Visitor;
-
-/// Strip all values with a unit type in positive (non-return) position
-pub(crate) struct StripPositiveUnits {}
-
-impl<'a, 'ast> Visitor<'a, 'ast, ast::Type<'ast>> for StripPositiveUnits {
-    type Error = Void;
-
-    fn pre_visit_expr(
-        &mut self,
-        expr: &mut Expr<'ast, ast::Type<'ast>>,
-    ) -> Result<(), Self::Error> {
-        let mut extracted = vec![];
-        if let Expr::Call { args, .. } = expr {
-            // TODO(grfn): replace with drain_filter once it's stabilized
-            let mut i = 0;
-            while i != args.len() {
-                if args[i].type_() == &ast::Type::Unit {
-                    let expr = args.remove(i);
-                    if !matches!(expr, Expr::Literal(Literal::Unit, _)) {
-                        extracted.push(expr)
-                    };
-                } else {
-                    i += 1
-                }
-            }
-        }
-
-        if !extracted.is_empty() {
-            let body = mem::replace(expr, Expr::Literal(Literal::Unit, ast::Type::Unit));
-            *expr = Expr::Let {
-                bindings: extracted
-                    .into_iter()
-                    .map(|expr| Binding {
-                        ident: Ident::from_str_unchecked("___discarded"),
-                        type_: expr.type_().clone(),
-                        body: expr,
-                    })
-                    .collect(),
-                type_: body.type_().clone(),
-                body: Box::new(body),
-            };
-        }
-
-        Ok(())
-    }
-
-    fn post_visit_call(
-        &mut self,
-        _fun: &mut Expr<'ast, ast::Type<'ast>>,
-        _type_args: &mut HashMap<Ident<'ast>, ast::Type<'ast>>,
-        args: &mut Vec<Expr<'ast, ast::Type<'ast>>>,
-    ) -> Result<(), Self::Error> {
-        args.retain(|arg| arg.type_() != &ast::Type::Unit);
-        Ok(())
-    }
-
-    fn visit_type(&mut self, type_: &mut ast::Type<'ast>) -> Result<(), Self::Error> {
-        if let ast::Type::Function(ft) = type_ {
-            ft.args.retain(|a| a != &ast::Type::Unit);
-        }
-        Ok(())
-    }
-
-    fn post_visit_fun_decl(
-        &mut self,
-        _name: &mut Ident<'ast>,
-        _type_args: &mut Vec<Ident>,
-        args: &mut Vec<(Ident, ast::Type<'ast>)>,
-        _body: &mut Box<Expr<ast::Type<'ast>>>,
-        _type_: &mut ast::Type<'ast>,
-    ) -> Result<(), Self::Error> {
-        args.retain(|(_, ty)| ty != &ast::Type::Unit);
-        Ok(())
-    }
-}
-
-pub(crate) fn run_toplevel<'a>(toplevel: &mut Vec<Decl<'a, ast::Type<'a>>>) {
-    let mut pass = StripPositiveUnits {};
-    for decl in toplevel.iter_mut() {
-        pass.visit_decl(decl).void_unwrap();
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::parser::toplevel;
-    use crate::tc::typecheck_toplevel;
-    use pretty_assertions::assert_eq;
-
-    #[test]
-    fn unit_only_arg() {
-        let (_, program) = toplevel(
-            "ty f : fn () -> int
-             fn f _ = 1
-
-             ty main : fn -> int
-             fn main = f ()",
-        )
-        .unwrap();
-
-        let (_, expected) = toplevel(
-            "ty f : fn -> int
-             fn f = 1
-
-             ty main : fn -> int
-             fn main = f()",
-        )
-        .unwrap();
-        let expected = typecheck_toplevel(expected).unwrap();
-
-        let mut program = typecheck_toplevel(program).unwrap();
-        run_toplevel(&mut program);
-
-        assert_eq!(program, expected);
-    }
-
-    #[test]
-    fn unit_and_other_arg() {
-        let (_, program) = toplevel(
-            "ty f : fn (), int -> int
-             fn f _ x = x
-
-             ty main : fn -> int
-             fn main = f () 1",
-        )
-        .unwrap();
-
-        let (_, expected) = toplevel(
-            "ty f : fn int -> int
-             fn f x = x
-
-             ty main : fn -> int
-             fn main = f 1",
-        )
-        .unwrap();
-        let expected = typecheck_toplevel(expected).unwrap();
-
-        let mut program = typecheck_toplevel(program).unwrap();
-        run_toplevel(&mut program);
-
-        assert_eq!(program, expected);
-    }
-
-    #[test]
-    fn unit_expr_and_other_arg() {
-        let (_, program) = toplevel(
-            "ty f : fn (), int -> int
-             fn f _ x = x
-
-             ty g : fn int -> ()
-             fn g _ = ()
-
-             ty main : fn -> int
-             fn main = f (g 2) 1",
-        )
-        .unwrap();
-
-        let (_, expected) = toplevel(
-            "ty f : fn int -> int
-             fn f x = x
-
-             ty g : fn int -> ()
-             fn g _ = ()
-
-             ty main : fn -> int
-             fn main = let ___discarded = g 2 in f 1",
-        )
-        .unwrap();
-        assert_eq!(expected.len(), 6);
-        let expected = typecheck_toplevel(expected).unwrap();
-
-        let mut program = typecheck_toplevel(program).unwrap();
-        run_toplevel(&mut program);
-
-        assert_eq!(program, expected);
-    }
-}