Appendix for Yasnippets

lp-in-org.org

@@ -169,6 +169,30 @@ Note: If you are reading this in an Emacs buffer, you can also place your cursor
 At this point, you can begin a line with =<s= and hit ~TAB~ to have a src block expanded, with the cursor left at the end of first line, allowing you to type =emacs-lisp=.
 
 This is Emacs, you probably have your favorite template expansion, like [[https://elpa.gnu.org/packages/doc/tempel/tempel.html][TempEL]] or [[https://www.emacswiki.org/emacs/Yasnippet][Yasnippet]], as any system that can generate your text works fine.The magic isn’t hidden in markers, but shines plainly in the text itself.
+** Editing src Blocks
+
+I find editing prose in an Org file quite nice…editing code? Not so much. Many techniques you expect to use, like jumping to code definitions with the [[info:emacs#Looking Up Identifiers][Xref system]] or manipulating s-expressions in a Lisp with =paredit= or =smart-parens=, aren’t available.
+
+With your cursor anywhere, the header line, anywhere in the body or one the =end_src= line, type ~C-c '~ to narrow to contents of that block with a mode based on the language on the header line.
+
+Whew, now you can edit your code in a manner you expect. Type ~C-c '~ again to save and return to your full org buffer, or ~C-c C-k~ to cancel your changes.
+
+Let’s add more [[info:org#Languages][languages]] to what is available, by running the following code:
+
+#+begin_src emacs-lisp
+  (org-babel-do-load-languages
+   'org-babel-load-languages
+   '((emacs-lisp . t)
+     (python . t)))
+#+end_src
+
+Feel free to substitute the =python=, for your favorite language, or add more. Use =sh= for shell scripts, and =js= for Javascript. See [[https://orgmode.org/worg/org-contrib/babel/languages/index.html][Babel]] for details on languages that can be supported.
+
+*Note:* If you don’t see you language’s pretty colors for its syntax, run this code (and put it in your init file):
+
+#+begin_src emacs-lisp
+  (setq org-src-fontify-natively t)
+#+end_src
 
 * Working with Python
 * Calling out to the Shell
@@ -177,3 +201,50 @@ Can we do both Bash, Fish and Powershell?
 ** Graphviz
 ** PlantUML
 ** Pikchr
+* Tips and Tricks
+This final chapter contains optional information you might find useful.
+
+Oh, and please let me know if you have a tip or trick that you think should be included.
+** Yasnippet Templates
+
+If you use [[https://www.emacswiki.org/emacs/Yasnippet][Yasnippet]], and include the [[https://github.com/AndreaCrotti/yasnippet-snippets][yasnippet-snippets project]], you can type =<s= in an Org buffer to expand into a src block, and type =def= in an Emacs Lisp buffer to get a function definition, but why not have both?
+
+In an Org file, type ~M-x yas-new-snippet~ and replace the default text with:
+
+#+begin_example
+  # key: #slf
+  # name: emacs-lisp-defun
+  # --
+  ,#+BEGIN_SRC emacs-lisp
+  (defun ${1:fun} (${2:args})
+    "${3:docstring}"
+    ${4:(interactive${5: "${6:P}"})}
+    $0)
+  ,#+END_SRC
+#+end_example
+
+Type ~C-c C-c~ to save and install the snippet with Org.
+
+Let’s make one for variables:
+
+#+begin_example
+  # key: slv
+  # name: emacs-lisp-defvar
+  # --
+  ,#+BEGIN_SRC emacs-lisp
+  (defvar ${1:symbol} ${2:initvalue} "${3:docstring}")
+  ,#+END_SRC
+#+end_example
+
+And maybe another one for defining unit tests?
+
+#+begin_example
+  # -*- mode: snippet -*-
+  # name: ert-deftest
+  # key: edt
+  # --
+  ,#+BEGIN_SRC emacs-lisp :tangle no
+  (ert-deftest $1-test ()
+    (should (= $0)))
+  ,#+END_SRC
+#+end_example