[elpa] master 85a43ad 35/40: Explain about backquote expressions in doc

[Noam Postavsky]

branch: master
commit 85a43ad8e5981b75945a87df162e210bea8947dc
Author: Noam Postavsky <address@hidden>
Commit: Noam Postavsky <address@hidden>

    Explain about backquote expressions in doc
    
    * doc/snippet-development.org (Embedded Emacs-lisp code): Add a subsection
    explaining that backquote expressions should not modify the buffer.
---
 doc/snippet-development.org |   23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/doc/snippet-development.org b/doc/snippet-development.org
index 4fd293d..ffe648c 100644
--- a/doc/snippet-development.org
+++ b/doc/snippet-development.org
@@ -209,7 +209,7 @@ back-quotes (=`=). The lisp forms are evaluated when the 
snippet is
 being expanded. The evaluation is done in the same buffer as the
 snippet being expanded.
 
-Here's an example for c-mode` to calculate the header file guard
+Here's an example for c-mode to calculate the header file guard
 dynamically:
 
 #+BEGIN_SRC snippet
@@ -235,6 +235,27 @@ to "wrap" the selected region inside your recently 
inserted snippet.
 Alternatively, you can also customize the variable
 [[sym:yas-wrap-around-region][=yas-wrap-around-region=]] to =t= which will do 
this automatically.
 
+*** Note: backquote expressions should not modify the buffer
+
+Please note that the lisp forms in backquotes should *not* modify the
+buffer, doing so will trigger a warning.  For example, instead of
+doing
+
+#+BEGIN_SRC snippet
+  Timestamp: `(insert (current-time-string))`
+#+END_SRC
+
+do this:
+#+BEGIN_SRC snippet
+  Timestamp: `(current-time-string)`
+#+END_SRC
+
+The warning may be suppressed with the following code in your init file:
+#+BEGIN_SRC emacs-lisp
+  (add-to-list 'warning-suppress-types '(yasnippet backquote-change))
+#+END_SRC
+
+
 ** Tab stop fields
 
 Tab stops are fields that you can navigate back and forth by =TAB= and