Merge pull request #21 from tarides/some-merlin-missing-pieces

Add `type-expression` (that allows to write an expression to type)

Author: xvw

README.md

@@ -43,8 +43,8 @@ navigating through errors:
 In `ocaml-eglot` one can display the type of the expression below the cursor and
 navigate the enclosing nodes while increasing or decreasing verbosity:
 
-- `ocaml-eglot-type-enclosing` (<kbd>C-c</kbd> <kbd>C-t</kbd>)
-Display the type of the selection and start a "type enclosing" session.
+- `ocaml-eglot-type-enclosing` (<kbd>C-c</kbd> <kbd>C-t</kbd>):
+display the type of the selection and start a "type enclosing" session.
 
 During a "type enclosing" session the following commands are available:
 
@@ -59,6 +59,12 @@ During a "type enclosing" session the following commands are available:
   expression
 - `ocaml-eglot-type-enclosing-copy` (<kbd>C-w</kbd>): to copy the
   type expression to the _kill-ring_ (clipboard)
+  
+You can also enter an expression in the mini-buffer for which you want
+to display the type:
+  
+- `ocaml-eglot-type-expression` (<kbd>C-u</kbd> <kbd>C-c</kbd> <kbd>C-t</kbd>)
+  
 
 ![Type Enclosings example](media/type-enclosing.gif)
 

ocaml-eglot-req.el

@@ -196,10 +196,17 @@ ARGV is the list of arguments."
 
 (defun ocaml-eglot-req--phrase (target)
   "Compute the beginning of the phrase referenced by TARGET."
-  ; TODO: use a dedicated custom request instead of tunneling
+  ;; TODO: use a dedicated custom request instead of tunneling
   (let ((argv (vector "-position" (ocaml-eglot-util-point-as-arg (point))
                       "-target" target)))
     (ocaml-eglot-req--merlin-call "phrase" argv)))
 
+(defun ocaml-eglot-req--type-expression (expression)
+  "Get the type of EXPRESSION inside the local context."
+  ;; TODO: use a dedicated custom request instead of tunneling
+  (let ((argv (vector "-position" (ocaml-eglot-util-point-as-arg (point))
+                      "-expression" expression)))
+    (ocaml-eglot-req--merlin-call "type-expression" argv)))
+
 (provide 'ocaml-eglot-req)
 ;;; ocaml-eglot-req.el ends here

ocaml-eglot.el

@@ -473,11 +473,23 @@ It use the ARG to use local values or not."
 
 ;; Type Enclosings
 
-(defun ocaml-eglot-type-enclosing ()
+(defun ocaml-eglot-type-expression (expression)
+  "Prompt the user for expression EXPRESSION and print its type."
+  (interactive "sExpression: ")
+  (let* ((result (ocaml-eglot-req--type-expression expression))
+         (type-expr (ocaml-eglot-util--merlin-call-result result)))
+    (ocaml-eglot-type-enclosing--display type-expr nil)))
+
+(defun ocaml-eglot-type-enclosing (&optional prefix)
   "Print the type of the expression under point (or of the region, if it exists).
-If called repeatedly, increase the verbosity of the type shown."
-  (interactive)
-  (ocaml-eglot-type-enclosing--call))
+If called repeatedly, increase the verbosity of the type shown.
+if PREFIX is given, prompt the user for expression EXPRESSION
+and print its type."
+  (interactive "P")
+  (if prefix
+      (call-interactively #'ocaml-eglot-type-expression)
+    (ocaml-eglot-type-enclosing--call)))
+
 
 ;; Case Analysis