Parser now prints an IN:/USING: form if restarts were invoked; add more restarts for certain errors

basis/prettyprint/prettyprint.factor

@@ -7,7 +7,7 @@ prettyprint.config sorting splitting grouping math.parser vocabs
 definitions effects classes.builtin classes.tuple io.files
 classes continuations hashtables classes.mixin classes.union
 classes.intersection classes.predicate classes.singleton
-combinators quotations sets accessors colors ;
+combinators quotations sets accessors colors parser ;
 IN: prettyprint
 
 : make-pprint ( obj quot -- block in use )
@@ -48,6 +48,22 @@ IN: prettyprint
     dupd remove [ { "syntax" "scratchpad" } member? not ] filter
     use. in. ;
 
+: vocab-names ( words -- vocabs )
+    dictionary get
+    [ [ words>> eq? nip ] with assoc-find 2drop ] curry map sift ;
+
+: prelude. ( -- )
+    in get use get vocab-names vocabs. ;
+
+[
+    nl
+    "Restarts were invoked adding vocabularies to the search path." print
+    "To avoid doing this in the future, add the following USING:" print
+    "and IN: forms at the top of the source file:" print nl
+    prelude.
+    nl
+] print-use-hook set-global
+
 : with-use ( obj quot -- )
     make-pprint vocabs. do-pprint ; inline
 

core/parser/parser.factor

@@ -52,7 +52,12 @@ SYMBOL: in
 
 M: parsing-word stack-effect drop (( parsed -- parsed )) ;
 
-ERROR: no-current-vocab ;
+TUPLE: no-current-vocab ;
+
+: no-current-vocab ( -- vocab )
+    \ no-current-vocab boa
+    { { "Define words in scratchpad vocabulary" "scratchpad" } }
+    throw-restarts dup set-in ;
 
 : current-vocab ( -- str )
     in get [ no-current-vocab ] unless* ;
@@ -64,20 +69,31 @@ ERROR: no-current-vocab ;
 
 : CREATE-WORD ( -- word ) CREATE dup reset-generic ;
 
-: word-restarts ( possibilities -- restarts )
+: word-restarts ( possibilities name -- restarts )
-    natural-sort [
+    [
+        natural-sort
         [
-            "Use the " swap vocabulary>> " vocabulary" 3append
+            [ "Use the " swap vocabulary>> " vocabulary" 3append ] keep
-        ] keep
+        ] { } map>assoc
-    ] { } map>assoc ;
+    ]
+    [ "Defer word in current vocabulary" swap 2array ] bi*
+    suffix ;
 
 ERROR: no-word-error name ;
 
+SYMBOL: amended-use?
+
+: no-word-restarted ( restart-value -- word )
+    dup word?
+    [ amended-use? on dup vocabulary>> (use+) ]
+    [ create-in ]
+    if ;
+
 : no-word ( name -- newword )
     dup \ no-word-error boa
-    swap words-named [ forward-reference? not ] filter
+    swap [ words-named [ forward-reference? not ] filter ] keep
     word-restarts throw-restarts
-    dup vocabulary>> (use+) ;
+    no-word-restarted ;
 
 : check-forward ( str word -- word/f )
     dup forward-reference? [
@@ -127,7 +143,9 @@ ERROR: staging-violation word ;
 : parsed ( accum obj -- accum ) over push ;
 
 : (parse-lines) ( lexer -- quot )
-    [ f parse-until >quotation ] with-lexer ;
+    [
+        f parse-until >quotation
+    ] with-lexer ;
 
 : parse-lines ( lines -- quot )
     lexer-factory get call (parse-lines) ;
@@ -206,8 +224,18 @@ SYMBOL: interactive-vocabs
         call
     ] with-scope ; inline
 
+SYMBOL: print-use-hook
+
+[ ] print-use-hook set-global
+
 : parse-fresh ( lines -- quot )
-    [ parse-lines ] with-file-vocabs ;
+    [
+        amended-use? off
+        parse-lines
+        amended-use? get [
+            print-use-hook get call
+        ] when
+    ] with-file-vocabs ;
 
 : parsing-file ( file -- )
     "quiet" get [