Make study a negatable option instead

README.asciidoc

@@ -109,7 +109,7 @@ as a key.
 
 Represents the pattern that things are matched against, constructed with
 `initRegex(string)` or `re(string)`. Examples: `re"foo"`, `re(r"foo # comment",
-"Sx<anycrlf>")`.
+"x<anycrlf>")`. 
 
 `pattern: string` :: the string that was used to create the pattern.
 `captureCount: int` :: the number of captures that the pattern has.
@@ -127,8 +127,6 @@ Represents the pattern that things are matched against, constructed with
    subject string
  - `N` - turn off auto-capture, `(?foo)` is necessary to capture.
  - `s` - `.` matches newline
- - `S` - study the pattern to hopefully improve performance. JIT is unspported at
-   the moment.
  - `U` - expressions are not greedy by default. `?` can be added to a qualifier
    to make it greedy.
  - `u` - same as `8`
@@ -152,3 +150,4 @@ ____
  - `<bsr_anycrlf>` - `\R` matches CR, LF, or CRLF
  - `<bsr_unicode>` - `\R` matches any unicode newline
  - `<js>` - Javascript compatibility
+ - `<no_study>` - turn off studying; study is enabled by deafault

test/find.nim

@@ -4,12 +4,12 @@ include nre
 suite "find":
   test "find text":
     check("3213a".find(initRegex(r"[a-z]")).match == "a")
-    check("1 2 3 4 5 6 7 8 ".findAll(initRegex(r" ", "S")).map(
+    check("1 2 3 4 5 6 7 8 ".findAll(re" ").map(
       proc (a: RegexMatch): string = a.match
     ) == @[" ", " ", " ", " ", " ", " ", " ", " "])
 
   test "find bounds":
-    check("1 2 3 4 5 ".findAll(initRegex(r" ", "S")).map(
+    check("1 2 3 4 5 ".findAll(re" ")).map(
       proc (a: RegexMatch): Slice[int] = a.matchBounds
     ) == @[1..2, 3..4, 5..6, 7..8, 9..10])
 

test/split.nim

@@ -4,9 +4,9 @@ include nre
 suite "string splitting":
   test "splitting strings":
     check("12345".split(initRegex("")) == @["1", "2", "3", "4", "5"])
-    check("1 2 3 4 5 6 ".split(initRegex(" ", "S")) == @["1", "2", "3", "4", "5", "6", ""])
-    check("1  2  ".split(initRegex(" ", "S")) == @["1", "", "2", "", ""])
-    check("1 2".split(initRegex(" ", "S")) == @["1", "2"])
+    check("1 2 3 4 5 6 ".split(re" ") == @["1", "2", "3", "4", "5", "6", ""])
+    check("1  2  ".split(initRegex(" ")) == @["1", "", "2", "", ""])
+    check("1 2".split(initRegex(" ")) == @["1", "2"])
     check("foo".split(initRegex("foo")) == @["", ""])
 
   test "captured patterns":