Make TildePrefix.recognize aware of its surroundings

src/prelexerState.ml

@@ -188,7 +188,7 @@ let string_of_word (Word (s, _)) = s
 
 let string_of_attribute = function
   | NoAttribute -> ""
-  | ParameterLength -> "#" 
+  | ParameterLength -> "#"
   | UseDefaultValues (p, w) -> p ^ string_of_word w
   | AssignDefaultValues (p, w) -> p ^ string_of_word w
   | IndicateErrorifNullorUnset (p, w) -> p ^ string_of_word w
@@ -366,7 +366,7 @@ let return ?(with_newline=false) lexbuf (current : prelexer_state) tokens =
             | QuotingMark _ -> []
           ) (buffer current)))
       in
-      let csts = TildePrefix.recognize csts in
+      let csts = TildePrefix.recognize ~in_assignment:false csts in (* FIXME: sometimes should be true *)
       [Pretoken.PreWord (w, csts)]
   in
   let tokens = if with_newline then tokens @ [Pretoken.NEWLINE] else tokens in

src/tildePrefix.ml

@@ -121,12 +121,10 @@ let rec concat_words_with_colon (words : word_cst list) : word_cst =
 (** Recognises tilde prefixes in a word, that is recognises eg. [WordLiteral
     "~foo"] and replaces it by [WordTildePrefix "foo"] when in the right
     position. *)
-let recognize (word : word_cst) =
-  match word with
-  | [WordAssignmentWord (name, Word (s, word))] ->
+let recognize ~in_assignment (word : word_cst) =
+  if in_assignment then
     let words = split_word_on_colon word in
     let words = List.map extract_tilde_prefix_from_word_if_present words in
-    let word = concat_words_with_colon words in
-    [WordAssignmentWord (name, Word (s, word))]
-  | _ ->
+    concat_words_with_colon words
+  else
     extract_tilde_prefix_from_word_if_present word