[elpa] externals/xr 8d052d6 09/13: Check for errors in \_

[Mattias Engdegård]

branch: externals/xr
commit 8d052d617f1e604143856b3b2b6657cac707d4c6
Author: Mattias Engdegård <address@hidden>
Commit: Mattias Engdegård <address@hidden>

    Check for errors in \_
---
 xr-test.el |  1 +
 xr.el      | 14 +++++++++++---
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/xr-test.el b/xr-test.el
index bd04bcb..7929e2a 100644
--- a/xr-test.el
+++ b/xr-test.el
@@ -75,6 +75,7 @@
                  '(seq bol nonl wordchar not-wordchar bos eos point
                        word-boundary not-word-boundary bow eow
                        symbol-start symbol-end eol)))
+  (should-error (xr "\\_a"))
   )
 
 (ert-deftest xr-syntax ()
diff --git a/xr.el b/xr.el
index 3133906..d7d28e3 100644
--- a/xr.el
+++ b/xr.el
@@ -356,7 +356,7 @@
 
        ;; various simple substitutions
        ((looking-at (rx (or "." "\\w" "\\W" "\\`" "\\'" "\\="
-                            "\\b" "\\B" "\\<" "\\>" "\\_<" "\\_>")))
+                            "\\b" "\\B" "\\<" "\\>")))
         (goto-char (match-end 0))
         (let ((sym (cdr (assoc
                          (match-string 0)
@@ -365,10 +365,18 @@
                            ("\\`" . bos) ("\\'" . eos)
                            ("\\=" . point)
                            ("\\b" . word-boundary) ("\\B" . not-word-boundary)
-                           ("\\<" . bow) ("\\>" . eow)
-                           ("\\_<" . symbol-start) ("\\_>" . symbol-end))))))
+                           ("\\<" . bow) ("\\>" . eow))))))
           (push sym sequence)))
 
+       ;; symbol-start, symbol-end
+       ((looking-at (rx "\\_" (opt (group (any "<>")))))
+        (let ((arg (match-string 1)))
+          (unless arg
+            (error "Invalid \\_ sequence"))
+          (forward-char 3)
+          (push (if (string-equal arg "<") 'symbol-start 'symbol-end)
+                sequence)))
+
        ;; character syntax
        ((looking-at (rx "\\" (group (any "sS")) (group anything)))
         (let ((negated (string-equal (match-string 1) "S"))