A presentation at RDG Geek Night in in Reading, UK by Drew McLellan
-HOW WE WROTE A- TEMPLATE ENGINE Drew McLellan Perch CMS grabaperch.com RDG Geek Night 10th September 2013
L I G H T W E I G H T PHP CMS FOR SMALL WEBSITES
WE NEEDED A REALLY GOOD TEMPLATE LANGUAGE
-SO- WHAT WAS ALREADY OUT THERE?
SMARTY (NOT SO SMART)
TWIG (NOT SO MATURE)
JUST PHP -WITH A- DIFFERENT SYNTAX
!<perch:content !!!type=”text” !!!id=”heading” !!!label=”Main heading” !!!required=”true” />
HTML IS LIKE XML RIGHT?
<img src="<perch:content id="photo" type="image" label="Photo" />" />
xkcd.com/208
stackoverflow.com/questions/1732348/
! <perch:content type=”text” ! ! id=”heading” label=”Main heading” ! ! required=”true” /> #perch:content[^]*/>#
$Tag = new PerchXMLTag( '<perch:content id="foo" bar="baz" />'); echo $Tag->bar; // baz
#([a-z-])="([^"])"#
#([a-z-]+)=["]([^"\ \](?:\\.[^"\\ ])*)["]#
-WAIT- REGULAR EXPRESSIONS ARE SLOW, RIGHT?
REGEX ARE SLOW UNLESS YOU NEED THEM
! <perch:if exists=”foo”> ! ! ... loadsamarkup ... ! </perch:if> #(perch:if[^]>)(((?! perch:if).))</perch:if>#
-WE NEEDED- A NEW WAY -TO PARSE- TAG PAIRS
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! <perch:if exists=”c”> ! ! ! Hello, world. ! ! </perch:if> ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! ! ! ! Hello, world. ! ! ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
<perch:if exists=”a”> ! <perch:if exists=”b”> ! ! ! ! ! Hello, world. ! ! ! </perch:if> <perch:else /> ! <perch:if exists=”d”> ! ! Goodbye, cruel world. ! </perch:if> </perch:if>
CLOSING TAGS -ARE - EASY
NO MORE WINDOWS CRASHES
MAYBE - WE WILL - REWRITE IT
THANK YOU Perch is at grabaperch.com On most things, I’ am @drewm
How we wrote a template engine for Perch CMS
