Building a toy template engine in Python

#1

Post by alexmic » Thu, Apr 11, 2013, 9:57 PM UTC

Building a toy template engine in Python
alexmic.net

Re: Building a toy template engine in Python

#2

Post by fredsters_s » Thu, Apr 11, 2013, 10:01 PM UTC

really nice conceptual approach.

Re: Building a toy template engine in Python

#3

Post by marinos » Thu, Apr 11, 2013, 10:50 PM UTC

thanks for sharing this alexmic. I tried to built my own template engine but I think your approach is much better

Re: Building a toy template engine in Python

#4

Post by alexmic » Thu, Apr 11, 2013, 10:58 PM UTC

marinos wrote: post #3

thanks for sharing this alexmic. I tried to built my own template engine but I think your approach is much better

Thanks – what was your approach?

Re: Building a toy template engine in Python

#5

Post by js2 » Fri, Apr 12, 2013, 12:43 AM UTC

A nice complement to this article is http://effbot.org/zone/simple-top-down-parsing.htm and its earlier piece http://effbot.org/zone/simple-iterator-parser.htm

Also, this page maintains links to many python parsing options - http://nedbatchelder.com/text/python-parsers.html

Re: Building a toy template engine in Python

#6

Post by peter_l_downs » Fri, Apr 12, 2013, 2:23 AM UTC

Great blog post! I did something very similar when I was working on an implementation of the Mustache templating language. If you haven't built a simple recursive descent parser already, I highly recommend doing so — it helped me get a lot better at programming.

Re: Building a toy template engine in Python

#7

Post by paradox95 » Fri, Apr 12, 2013, 2:40 AM UTC

Try Pyxl

https://github.com/dropbox/pyxl

I don't work at Dropbox but I did work at Cove where this was originally developed and it is great. Makes working with HTML in Python so easy.

I also my own version of it that I have rewritten to treat the HTML object more like jQuery does and added more jQuery methods to it.

Re: Building a toy template engine in Python

#8

Post by thomaslee » Fri, Apr 12, 2013, 5:36 AM UTC

Interesting extension of this exercise would be to replace your custom AST with the AST exposed by Python, then use the compile() builtin to compile said AST into a PyCodeObject ready for direct execution by the Python VM. :)

Something along these lines: https://github.com/thomaslee/viking-poc/blob/master/viking#L...

(Disclaimer: I wrote the Python-AST-to-PyObject transformation code for Python 2.6 that made this sort of stuff possible -- fun hack!)

Re: Building a toy template engine in Python

#9

Post by thisishugo » Fri, Apr 12, 2013, 8:52 AM UTC

I'm not sure I like the idea of parsing templates with regular expressions. There is a better way, as demonstrated in Robe Pike's video[1] detailing how the Go template language is implemented.

Edit: which isn't meant to detract from the fact that this is a great article.

[1]http://www.youtube.com/watch?v=HxaD_trXwRE

Re: Building a toy template engine in Python

#10

Post by alexmic » Fri, Apr 12, 2013, 9:35 AM UTC

thisishugo wrote: post #9

I'm not sure I like the idea of parsing templates with regular expressions. There is a better way, as demonstrated in Robe Pike's video[1] detailing how the Go template language is implemented. Edit: which isn't meant to detract from the fact that this is a great article. [1] http://www.youtube.com/watch?v=HxaD_trXwRE

Thanks for the video – this was my first stub at template engines so I'm all for learning about better approaches.