Update combinators test and improve docs

src/term/transform/float_combinators.rs

@@ -15,7 +15,8 @@ impl Book {
   ///
   /// The floating algorithm follows these rules:
   /// - Recursively float every child term.
-  /// - Extract if it is a combinator and not is a safe term.
+  /// - Extract if it is a combinator and is not a safe term.
+  /// See [`Term::is_safe`] for what is considered safe here.
   pub fn float_combinators(&mut self) {
     let mut combinators = Combinators::new();
 

tests/golden_tests/desugar_file/combinators.hvm

@@ -12,12 +12,14 @@
 
 (qux) = {0 qux}
 
+(clax) = (λx x λa λb λc λd (clax d))
+
 (tup) = (tup, 1, 0)
 
 (list) = [0 list]
 
-(A x) = (let {a b} = A; @c (a b c) x)
+(A x) = (let {a b} = A; λc (a b c) x)
 
-(B x) = (let (a, b) = B; @c (a b c) x)
+(B x) = (let (a, b) = B; λc (a b c) x)
 
 (Main) = list

tests/snapshots/desugar_file__combinators.hvm.snap

@@ -12,6 +12,8 @@ input_file: tests/golden_tests/desugar_file/combinators.hvm
 
 (qux) = {0 qux}
 
+(clax) = (λa a clax$C0)
+
 (tup) = (tup, 1, 0)
 
 (list) = (List.cons 0 list$C0)
@@ -32,4 +34,6 @@ input_file: tests/golden_tests/desugar_file/combinators.hvm
 
 (List.ignore$C0) = #List λ* #List λd (List.ignore d List.ignore)
 
+(clax$C0) = λ* λ* λ* λe (clax e)
+
 (list$C0) = (List.cons list List.nil)