From 619fbb921710fce5395a2e8b4e5a9d775dbcc00a Mon Sep 17 00:00:00 2001
From: Jay McCarthy <jay.mccarthy@gmail.com>
Date: Tue, 6 Oct 2015 14:37:14 -0400
Subject: [PATCH] demonstrating non-() stx

---
 remix/README           |  4 +++-
 remix/datalog0.rkt     | 24 ++++++++++++++++++++++
 remix/raw-stx0.rkt     | 45 ++++++++++++++++++++++++++++++++++++++++++
 remix/tests/simple.rkt | 18 ++++++++++++++---
 4 files changed, 87 insertions(+), 4 deletions(-)
 create mode 100644 remix/datalog0.rkt
 create mode 100644 remix/raw-stx0.rkt

diff --git a/remix/README b/remix/README
index f804d8b..faa8f8f 100644
--- a/remix/README
+++ b/remix/README
@@ -1,4 +1,6 @@
-TODO @ everywhere
+DONE @ everywhere
+
+DONE demonstrate how @ everywhere enables non-() macros like datalog
 
 DONE {} particular => (#%braces)
 
diff --git a/remix/datalog0.rkt b/remix/datalog0.rkt
new file mode 100644
index 0000000..6abcb9c
--- /dev/null
+++ b/remix/datalog0.rkt
@@ -0,0 +1,24 @@
+#lang racket/base
+(require datalog/runtime
+         (prefix-in stx: datalog/stx)
+         (for-syntax racket/base
+                     remix/raw-stx0
+                     datalog/private/compiler
+                     datalog/parse
+                     syntax/parse))
+
+(define-syntax (datalog stx)
+  (syntax-parse stx
+    [(_ thy:expr s:str ...)
+     (with-syntax
+       ([(stmt ...)
+         (compile-program
+          (parse-program
+           (syntax-strings->input-port
+            (syntax-source stx)
+            (syntax->list #'(s ...)))))])
+       (syntax/loc stx
+         (stx:datalog thy stmt ...)))]))
+
+(provide make-theory
+         datalog)
diff --git a/remix/raw-stx0.rkt b/remix/raw-stx0.rkt
new file mode 100644
index 0000000..68316da
--- /dev/null
+++ b/remix/raw-stx0.rkt
@@ -0,0 +1,45 @@
+#lang racket/base
+(require racket/match)
+
+(define (syntax-strings->input-port name ss)
+  (define line 1)
+  (define col 0)
+  (define pos 1)
+  (define current-idx #f)
+  (define current-bs #f)
+  (define next-ss ss)
+
+  (define (read-in bs)
+    (cond
+      [(not current-bs)
+       (match next-ss
+         ['() eof]
+         [(cons ss more-ss)
+          (set! line (syntax-line ss))
+          (set! col (syntax-column ss))
+          (set! pos (syntax-position ss))
+          (set! current-bs (string->bytes/utf-8 (syntax->datum ss)))
+          (set! current-idx 0)
+          (set! next-ss more-ss)
+          (read-in bs)])]
+      [(< current-idx (bytes-length current-bs))
+       (define how-many
+         (min (bytes-length bs)
+              (- (bytes-length current-bs)
+                 current-idx)))
+       (define end (+ current-idx how-many))
+       (bytes-copy! bs 0 current-bs current-idx end)
+       (set! current-idx end)
+       (set! col (+ col how-many))
+       (set! pos (+ pos how-many))
+       how-many]
+      [else
+       (set! current-bs #f)
+       (read-in bs)]))
+  (define (get-location)
+    (values line col pos))
+
+  (make-input-port name read-in #f void #f #f
+                   get-location void #f #f))
+
+(provide syntax-strings->input-port)
diff --git a/remix/tests/simple.rkt b/remix/tests/simple.rkt
index c87d9f2..cb5d1ab 100644
--- a/remix/tests/simple.rkt
+++ b/remix/tests/simple.rkt
@@ -6,9 +6,13 @@
   (def a 40)
   (def b 2)
   (+ a b))
+(module+ test
+  x)
 
 (def (f x y)
   (+ [(def z (+ x x)) z] y))
+(module+ test
+  (f x x))
 
 (def (g x)
   (cond
@@ -16,10 +20,18 @@
     (def z (/ x 2))
     [(< z 100) "div 100"]
     [#:else "other"]))
-
 (module+ test
-  x
-  (f x x)
   (g 50)
   (g 199)
   (g 200))
+
+(require remix/datalog0)
+(def graph (make-theory))
+@datalog[graph]{
+ edge(a, b). edge(b, c). edge(c, d). edge(d, a).
+ path(X, Y) :- edge(X, Y).
+ path(X, Y) :- edge(X, Z), path(Z, Y).
+ path(X, Y)?
+}
+
+