[elpa] 01/255: parsing properties in SGF files

[Eric Schulte]

eschulte pushed a commit to branch go
in repository elpa.

commit 66c3ac2c91b6b78de3db77dce7bffc00bb09450c
Author: Eric Schulte <address@hidden>
Date:   Tue May 15 00:31:48 2012 -0400

    parsing properties in SGF files
---
 sgf.el |   84 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 84 insertions(+), 0 deletions(-)

diff --git a/sgf.el b/sgf.el
new file mode 100644
index 0000000..3f2073d
--- /dev/null
+++ b/sgf.el
@@ -0,0 +1,84 @@
+;;; sgf.el --- Smart Game Format (focused on GO)
+
+;; http://www.red-bean.com/sgf/sgf4.html
+;; http://www.red-bean.com/sgf/properties.html
+
+;;; BNF
+;; Collection = GameTree { GameTree }
+;; GameTree   = "(" Sequence { GameTree } ")"
+;; Sequence   = Node { Node }
+;; Node       = ";" { Property }
+;; Property   = PropIdent PropValue { PropValue }
+;; PropIdent  = UcLetter { UcLetter }
+;; PropValue  = "[" CValueType "]"
+;; CValueType = (ValueType | Compose)
+;; ValueType  = (None | Number | Real | Double | Color | SimpleText |
+;;             Text | Point  | Move | Stone)
+
+;;; There are two types of property lists: 'list of' and 'elist of'. 
+;; 'list of':    PropValue { PropValue }
+;; 'elist of':   ((PropValue { PropValue }) | None)
+;;               In other words elist is list or "[]".
+
+;;; Property Value Types
+;; UcLetter   = "A".."Z"
+;; Digit      = "0".."9"
+;; None       = ""
+;; Number     = [("+"|"-")] Digit { Digit }
+;; Real       = Number ["." Digit { Digit }]
+;; Double     = ("1" | "2")
+;; Color      = ("B" | "W")
+;; SimpleText = { any character (handling see below) }
+;; Text       = { any character (handling see below) }
+;; Point      = game-specific
+;; Move       = game-specific
+;; Stone      = game-specific
+;; Compose    = ValueType ":" ValueType
+
+;; an example is at the bottom of the page
+
+;;; Comments:
+
+;; - an sgf tree is just a series of nested lists.
+;; - a pointer into the tree marks the current location
+;; - navigation using normal Sexp movement
+;; - games build such trees as they go
+;; - a board is just one interface into such a tree
+
+;;; Code:
+(defun char-to-offset (char)
+  (if (< char ?a)
+      (+ 26 (- char ?A))
+    (- char ?a)))
+
+(defun parse-prop (str)
+  (multiple-value-bind (id rest) (parse-prop-ident str)
+    (cons id (parse-prop-vals rest))))
+
+(defun parse-prop-ident (str)
+  (let ((end (if (and (<= ?A (aref str 1))
+                      (< (aref str 1) ?Z))
+                 2 1)))
+    (values (substring str 0 end)
+            (substring str end))))
+
+(defun parse-prop-vals (str)
+  (let (res (start 0))
+    (while (string-match "\\[\\(.*?[^\\]\\)\\]" str start)
+      (push (match-string 1 str) res)
+      (setq start (match-end 0)))
+    res))
+
+
+;;; Tests
+(require 'ert)
+
+(ert-deftest parse-prop-tests ()
+  (flet ((should= (a b) (should (tree-equal a b :test #'string=))))
+    (should= (parse-prop "B[pq]") '("B" "pq"))
+    (should= (parse-prop "GM[1]") '("GM" "1"))
+    (should (= (length (cdr (parse-prop "TB[as][bs][cq][cr][ds][ep]")))
+               6))))
+
+(defun parse-nodes (str)
+  )