Using current-read-interaction and renabling adapted tutorial

original commit: 8afc06c09679827189aa8f5918cb914f6a02d731

collects/datalog/lang/reader.rkt

@@ -11,8 +11,22 @@
            ; XXX Should have different comment character key
            (case key
              [(drracket:submit-predicate)
-              (dynamic-require `datalog/tool/submit 'repl-submit?)]
+              repl-submit?]
              [(color-lexer)
               (dynamic-require `datalog/tool/syntax-color 'get-syntax-token)]
              [else (default key defval)]))
-  (require "../parse.rkt"))
+  (require datalog/parse
+           datalog/tool/submit)
+  
+  ; XXX This is almost certainly wrong.
+  (define (even-read src ip)
+    (begin0
+      (parameterize ([current-source-name src])
+       (datum->syntax #f (parse-statement ip)))
+      (current-read-interaction odd-read)))
+  (define (odd-read src ip)
+    (current-read-interaction even-read)
+    eof)
+    
+  (current-read-interaction
+   even-read))

collects/datalog/parse.rkt

@@ -104,6 +104,7 @@ A Datalog reader consumes a Datalog program. A program is a sequence of zero or
 (define parse-program (mk-parser program-parser))
 
 (provide/contract
+ [current-source-name (parameter/c any/c)]
  [parse-literal (input-port? . -> . literal?)]
  [parse-clause (input-port? . -> . clause?)]
  [parse-statement (input-port? . -> . statement/c)]

collects/datalog/scribblings/datalog.scrbl

@@ -125,7 +125,9 @@ The following is a program:
 END
 ]
 
-Currently, REPL interaction is not supported.
+The Datalog REPL accepts new statements that are executed as if they were in the original program text.
+
+@include-section["tutorial.scrbl"]
 
 @section{Parenthetical Datalog Module Language}
 @(require (for-label datalog/sexp/lang))
@@ -152,6 +154,8 @@ The following is a program:
        (path ,Z ,Y)))
 (? (path ,X ,Y))]
 
+The Parenthetical Datalog REPL accepts new statements that are executed as if they were in the original program text.
+
 @subsection[#:tag "parenstx"]{Parenthetical Syntax}
 
 @defmodule[datalog/sexp/lang]

collects/datalog/scribblings/racket.scrbl

@@ -197,6 +197,8 @@ This library provides facilities for parsing Datalog source. It can be required
 
 @defmodule[datalog/parse]
 
+@defparam[current-source-name name any/c]{ A parameter used by the parsing functions to set the source name on the read ASTs. }
+
 @defproc[(parse-literal [ip input-port?])
          literal?]{
  Parses a @racket[literal] from @racket[ip].

collects/datalog/scribblings/tutorial.scrbl

@@ -10,9 +10,11 @@
 
 @title{Tutorial}
 
-Start DrScheme and choose the @tt{Datalog} language from DrScheme's
-@tt{Language} menu under @tt{Experimental Languages}. Click @onscreen{Run}, then
-click in the REPL.
+Start DrRacket and type
+
+@racketmod[datalog]
+
+in the Definitions window. Click @onscreen{Run}, then click in the REPL.
 
 @racketinput[]
 
@@ -72,7 +74,7 @@ C is an ancestor of B, then A is an ancestor of B.
              #,(tt "  parent(A, C),")
              #,(tt "  ancestor(C, B).")]
 
-In the interpreter, DrScheme knows that the clause is not complete, so by pressing Return, it doesn't interpret the line.
+In the interpreter, DrRacket knows that the clause is not complete, so by pressing Return, it doesn't interpret the line.
 
 Rules are used to answer queries just as is done for facts.