add some notes to but and with docs

src/primitive/defs.rs

@@ -1768,6 +1768,11 @@ primitive!(
  /// ex: # Experimental!
  /// : [⤙⊙⊙⊙∘ 1 2 3 4]
  /// : [⤙⊙⊙⊙◌ 1 2 3 4]
+ /// [but] always takes at least 2 arguments, even if its function takes fewer.
+ /// ex! # Experimental!
+ /// : [⤙¯ 2]
+ /// ex: # Experimental!
+ /// : [⤙¯ 2 5]
  ([1], But, Stack, ("but", '⤙')),
  /// Call a function but keep its first argument under the outputs on the stack
  ///
@@ -1778,6 +1783,11 @@ primitive!(
  /// ex: # Experimental!
  /// : [⤚⊙⊙⊙∘ 1 2 3 4]
  /// : [⤚⋅⊙⊙∘ 1 2 3 4]
+ /// [with] always takes at least 2 arguments, even if its function takes fewer.
+ /// ex! # Experimental!
+ /// : [⤚¯ 2]
+ /// ex: # Experimental!
+ /// : [⤚¯ 2 5]
  ([1], With, Stack, ("with", '⤚')),
  /// Duplicate a function's last argument before calling it
  ///