http://www.dzone.com/links/users/links/279649.html DZone: fresh links for developers en-us Copyright (c) 2006 DZone, Inc. Fri, 22 Aug 2008 04:25:49 GMT The DZone community 2008-08-22T04:25:49Z en-us Copyright (c) 2006 DZone, Inc. http://www.dzone.com/links/feed/user/279649/rss.xml http://www.dzone.com/images/std/dzone.com_258x55.gif http://www.dzone.com/links/ http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_8.html Part 8 adds support for assignment, and adds some minor runtime support (in C temporarily) for arithmetic and comparisons, and briefly discusses how to translate the C functions into primitives in the compiler in Ruby. how-to other languages ruby Mon, 02 Jun 2008 15:03:05 GMT http://www.dzone.com/links/84474.html vidarh 2008-06-02T15:03:05Z Part 8 adds support for assignment, and adds some minor runtime support (in C temporarily) for arithmetic and comparisons, and briefly discusses how to translate the C functions into primitives in the compiler in Ruby.]]> 84474 2008-06-02T15:03:05Z 4 0 10 0 http://www.dzone.com/links/images/thumbs/120x90/84474.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/traceviz_visualizing_traceroute_output_with_graph.html At one point I quickly hacked together a Ruby script to merge the paths generated by multiple traceroute runs together into directed graphs, showing the routing from a few selected host in our environment to all our other hosts. I generated dot-files suitable for GraphViz from it. Here's a rewrite and step by step instructions to turn it into nice SVG and/or bitmap diagrams. how-to ruby tools Thu, 29 May 2008 13:35:30 GMT http://www.dzone.com/links/83749.html vidarh 2008-05-29T13:35:30Z At one point I quickly hacked together a Ruby script to merge the paths generated by multiple traceroute runs together into directed graphs, showing the routing from a few selected host in our environment to all our other hosts. I generated dot-files suitable for GraphViz from it. Here's a rewrite and step by step instructions to turn it into nice SVG and/or bitmap diagrams.]]> 83749 2008-05-29T13:35:30Z 3 0 18 0 http://www.dzone.com/links/images/thumbs/120x90/83749.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/reducing_coupling_through_unit_tests.html After my previous post on the subject of coupling and cohesion, a lot of the feedback I've gotten has been from people who want examples of lowering coupling, or want to know how they can see if their code is loosely coupled. This post briefly gives some advice on how unit testing encourages structuring code in ways that tends to reduce coupling. how-to methodology opinion Fri, 23 May 2008 19:58:14 GMT http://www.dzone.com/links/82647.html vidarh 2008-05-23T19:58:14Z After my previous post on the subject of coupling and cohesion, a lot of the feedback I've gotten has been from people who want examples of lowering coupling, or want to know how they can see if their code is loosely coupled. This post briefly gives some advice on how unit testing encourages structuring code in ways that tends to reduce coupling.]]> 82647 2008-05-23T19:58:14Z 3 0 20 0 http://www.dzone.com/links/images/thumbs/120x90/82647.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_7.html Seventh in my series on writing a compiler in Ruby: Using lambda/call to implement control structures, and finally making it possible to access function arguments. how-to other languages ruby Fri, 16 May 2008 15:56:22 GMT http://www.dzone.com/links/81341.html vidarh 2008-05-16T15:56:22Z Seventh in my series on writing a compiler in Ruby: Using lambda/call to implement control structures, and finally making it possible to access function arguments.]]> 81341 2008-05-16T15:56:22Z 3 0 12 0 http://www.dzone.com/links/images/thumbs/120x90/81341.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/how_to_beat_comment_spam_for_now_anyway.html Thoughts on defeating comment spam without user visible captcha's by using javascript. how-to javascript opinion web 2.0 Thu, 15 May 2008 11:03:34 GMT http://www.dzone.com/links/81125.html vidarh 2008-05-15T11:03:34Z Thoughts on defeating comment spam without user visible captcha's by using javascript.]]> 81125 2008-05-15T11:03:34Z 2 0 17 0 http://www.dzone.com/links/images/thumbs/120x90/81125.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/a_brief_introduction_to_semantic_dictionary_encod.html SDE is, at it's most basic, a compression mechanism for the intermediate representation of a compiler. Similiarly to Huffman coding, an SDE encoder and decoder pair both builds a dictionary of the datastream while building it and decoding it respectively. The dictionary entries is the used to encode/decode the following part of the data stream, which cause more entries to be added to the dictionary, etc., meaning that the later you are in the data stream, the more of the stream will refer to previously added dictionary entries instead of having to be all verbose and include the full definition. But to call it just a compression method would be selling it very short. The appeal of SDE is that it can be used as a machine independent representation of a program, while at the same time it can (if used properly) retain far more semantic information about the program than a typical bytecode. Contrary to most bytecode, SDE retains the structure of the program as represented by the compiler. methodology other languages research Wed, 07 May 2008 15:04:32 GMT http://www.dzone.com/links/79739.html vidarh 2008-05-07T15:04:32Z SDE is, at it's most basic, a compression mechanism for the intermediate representation of a compiler. Similiarly to Huffman coding, an SDE encoder and decoder pair both builds a dictionary of the datastream while building it and decoding it respectively. The dictionary entries is the used to encode/decode the following part of the data stream, which cause more entries to be added to the dictionary, etc., meaning that the later you are in the data stream, the more of the stream will refer to previously added dictionary entries instead of having to be all verbose and include the full definition. But to call it just a compression method would be selling it very short. The appeal of SDE is that it can be used as a machine independent representation of a program, while at the same time it can (if used properly) retain far more semantic information about the program than a typical bytecode. Contrary to most bytecode, SDE retains the structure of the program as represented by the compiler.]]> 79739 2008-05-07T15:04:32Z 2 0 10 0 http://www.dzone.com/links/images/thumbs/120x90/79739.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_6.html Sixth in my series on writing a compiler in Ruby: "How about some deferred evaluation and anonymous functions? Lambdas, or anonymous functions, can be passed around like values and called at your convenience (or not at all). Generally, they can access variables from the surrounding scope that gets "bound" to the function as an environment that allows it to pass state. That's a closure. What we're going to do this time is not going to bring full closure support, but it's the start, and we'll get to full closures down the road." how-to other languages ruby Tue, 06 May 2008 13:25:59 GMT http://www.dzone.com/links/79080.html vidarh 2008-05-06T13:25:59Z Sixth in my series on writing a compiler in Ruby: "How about some deferred evaluation and anonymous functions? Lambdas, or anonymous functions, can be passed around like values and called at your convenience (or not at all). Generally, they can access variables from the surrounding scope that gets "bound" to the function as an environment that allows it to pass state. That's a closure. What we're going to do this time is not going to bring full closure support, but it's the start, and we'll get to full closures down the road."]]> 79080 2008-05-03T18:26:20Z 2008-05-06T13:25:59Z 5 0 142 0 http://www.dzone.com/links/images/thumbs/120x90/79080.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/software_ics_reuse_should_not_always_mean_inherit.html Inheritance or configuration options has a cost in terms of increased complexity that can in some cases with advantage be avoided by maintaining multiple versions of the component and adding new features to new branches instead of continuing to work on a single code base, in the same way integrated circuits often exist in a wide range of similar, static, models with the same basic functionality. Better merging support in modern version control systems make this model increasingly viable for software. methodology opinion tools Thu, 01 May 2008 21:51:05 GMT http://www.dzone.com/links/78833.html vidarh 2008-05-01T21:51:05Z Inheritance or configuration options has a cost in terms of increased complexity that can in some cases with advantage be avoided by maintaining multiple versions of the component and adding new features to new branches instead of continuing to work on a single code base, in the same way integrated circuits often exist in a wide range of similar, static, models with the same basic functionality. Better merging support in modern version control systems make this model increasingly viable for software.]]> 78833 2008-05-01T21:51:05Z 1 0 8 0 http://www.dzone.com/links/images/thumbs/120x90/78833.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/customizing_the_ruby_syntax_highlighter_for_x86_a.html I wrote about syntax hightlighting in Ruby a while ago. The Ruby Syntax library supports Ruby, YAML and XML out of the box. But it's also pretty easy to extend to handle other languages. Since I've been writing my compiler in Ruby series and including a lot of x86 assembler, I figured I'd see how much (or little) work adding a syntax highlighter for assembler would take how-to other languages ruby Wed, 30 Apr 2008 18:05:44 GMT http://www.dzone.com/links/78608.html vidarh 2008-04-30T18:05:44Z I wrote about syntax hightlighting in Ruby a while ago. The Ruby Syntax library supports Ruby, YAML and XML out of the box. But it's also pretty easy to extend to handle other languages. Since I've been writing my compiler in Ruby series and including a lot of x86 assembler, I figured I'd see how much (or little) work adding a syntax highlighter for assembler would take]]> 78608 2008-04-30T18:05:44Z 2 0 12 0 http://www.dzone.com/links/images/thumbs/120x90/78608.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/rebuilding_the_build_server_on_every_build.html I argue that with virtualization, there's a lot of compelling reasons and few downsides with not only rebuilding your applications from scratch regularly, but also rebuilding your _build server_ from scratch on every full build. methodology opinion tools unix-linux Mon, 21 Apr 2008 08:35:55 GMT http://www.dzone.com/links/76520.html vidarh 2008-04-21T08:35:55Z I argue that with virtualization, there's a lot of compelling reasons and few downsides with not only rebuilding your applications from scratch regularly, but also rebuilding your _build server_ from scratch on every full build.]]> 76520 2008-04-18T15:46:23Z 2008-04-21T08:35:55Z 6 0 356 3 http://www.dzone.com/links/images/thumbs/120x90/76520.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_4.html Fourth in a series on writing a compiler targeting x86. This part shows how to define functions, and adds a mechanism for adding a runtime library. how-to open source other languages ruby Sun, 20 Apr 2008 01:40:54 GMT http://www.dzone.com/links/76518.html vidarh 2008-04-20T01:40:54Z Fourth in a series on writing a compiler targeting x86. This part shows how to define functions, and adds a mechanism for adding a runtime library.]]> 76518 2008-04-18T15:43:46Z 2008-04-20T01:40:54Z 8 0 217 0 http://www.dzone.com/links/images/thumbs/120x90/76518.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/mini_reviews_of_19_ruby_template_engines.html I've seen lots of template systems in Ruby, but haven't been really been happy with any of them. Over the last few months or so I've kept notes of the ones I looked at. This is the list I came up with, and some comments on each. frameworks reviews ruby web design Sun, 13 Apr 2008 10:29:33 GMT http://www.dzone.com/links/75594.html vidarh 2008-04-13T10:29:33Z I've seen lots of template systems in Ruby, but haven't been really been happy with any of them. Over the last few months or so I've kept notes of the ones I looked at. This is the list I came up with, and some comments on each.]]> 75594 2008-04-12T12:04:49Z 2008-04-13T10:29:33Z 11 0 337 0 http://www.dzone.com/links/images/thumbs/120x90/75594.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_3.html Third in a series - this part covers chaining expressions and compiling sub-expressions, and also includes a list of the upcoming parts. This one's fairly short - the next ones will be longer, I promise... how-to other languages ruby Mon, 07 Apr 2008 01:45:48 GMT http://www.dzone.com/links/74434.html vidarh 2008-04-07T01:45:48Z Third in a series - this part covers chaining expressions and compiling sub-expressions, and also includes a list of the upcoming parts. This one's fairly short - the next ones will be longer, I promise...]]> 74434 2008-04-05T12:14:32Z 2008-04-07T01:45:48Z 7 0 372 0 http://www.dzone.com/links/images/thumbs/120x90/74434.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/making_graphviz_diagrams_pretty_with_xsl.html A couple of years back I posted on my blog about an XSL transformation I used to clean up Graphviz output to make my diagrams prettier. I never posted the XSL, though, but since I've dug it out again, here it is. It uses Graphviz' SVG output and transforms it to add dropshadows and gradients to the resulting diagrams, but can be easily used as an example of how to apply other changes to the Graphviz output how-to open source tools xml Tue, 01 Apr 2008 00:39:21 GMT http://www.dzone.com/links/73339.html vidarh 2008-04-01T00:39:21Z A couple of years back I posted on my blog about an XSL transformation I used to clean up Graphviz output to make my diagrams prettier. I never posted the XSL, though, but since I've dug it out again, here it is. It uses Graphviz' SVG output and transforms it to add dropshadows and gradients to the resulting diagrams, but can be easily used as an example of how to apply other changes to the Graphviz output]]> 73339 2008-03-30T13:38:30Z 2008-04-01T00:39:21Z 9 0 384 0 http://www.dzone.com/links/images/thumbs/120x90/73339.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/track_your_latest_referrers_using_rack_and_ruby.html As most bloggers I like to keep an eye on where my traffic is coming from, and especially when there are surges in traffic. I'm using both Google Analytics and Feedburner for stats, and it works great for trends, but not see what's happening right now. This morning I needed a distraction and figured I'd just throw together a quick and dirty Rack middleware class to keep track of the latest referrers. frameworks how-to open source ruby Sat, 29 Mar 2008 12:26:56 GMT http://www.dzone.com/links/73244.html vidarh 2008-03-29T12:26:56Z As most bloggers I like to keep an eye on where my traffic is coming from, and especially when there are surges in traffic. I'm using both Google Analytics and Feedburner for stats, and it works great for trends, but not see what's happening right now. This morning I needed a distraction and figured I'd just throw together a quick and dirty Rack middleware class to keep track of the latest referrers.]]> 73244 2008-03-29T12:26:56Z 3 0 22 0 http://www.dzone.com/links/images/thumbs/120x90/73244.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/why_coupling_is_always_bad_cohesion_vs_coupling.html In the discussion following my entry "Why Rails is total overkill and why I love Rack" several comments raised the issue of whether high coupling is always bad. My answer was that I believe it is, but at the same time it can be worth it _sometimes_. This post expands on that. frameworks opinion Fri, 28 Mar 2008 16:10:20 GMT http://www.dzone.com/links/73155.html vidarh 2008-03-28T16:10:20Z In the discussion following my entry "Why Rails is total overkill and why I love Rack" several comments raised the issue of whether high coupling is always bad. My answer was that I believe it is, but at the same time it can be worth it _sometimes_. This post expands on that.]]> 73155 2008-03-28T16:10:20Z 1 0 38 0 http://www.dzone.com/links/images/thumbs/120x90/73155.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/httpwwwhokstadcomwhycouplingisalwaysbadcohesionvs.html In the discussion following my entry "Why Rails is total overkill and why I love Rack" several comments raised the issue of whether high coupling is always bad. My answer was that I believe it is, but at the same time it can be worth it _sometimes_. This post expands on that. frameworks opinion Fri, 28 Mar 2008 16:09:15 GMT http://www.dzone.com/links/73154.html vidarh 2008-03-28T16:09:15Z In the discussion following my entry "Why Rails is total overkill and why I love Rack" several comments raised the issue of whether high coupling is always bad. My answer was that I believe it is, but at the same time it can be worth it _sometimes_. This post expands on that.]]> 73154 2008-03-28T16:09:15Z 0 0 0 2 http://www.dzone.com/links/images/thumbs/120x90/73154.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_2.html Second part of my series on writing a compiler targeting i386 in Ruby. This part adds support for function calls, so a simple hello world can be compiled. how-to other languages ruby Thu, 27 Mar 2008 17:07:29 GMT http://www.dzone.com/links/72974.html vidarh 2008-03-27T17:07:29Z Second part of my series on writing a compiler targeting i386 in Ruby. This part adds support for function calls, so a simple hello world can be compiled.]]> 72974 2008-03-27T17:07:29Z 3 0 28 0 http://www.dzone.com/links/images/thumbs/120x90/72974.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/writing_a_compiler_in_ruby_bottom_up_step_1.html This is part 1 in what will be a long series (ca. 30 parts written so far) about writing a small compiler in Ruby "bottom up", in other words starting with the code generator, rather than the more conventional approach of starting with the parser. The focus is not so much on Ruby as it is on how to build a code generator and how to implement low level features of a language in the simplest possible way. how-to other languages ruby Wed, 26 Mar 2008 20:58:36 GMT http://www.dzone.com/links/72627.html vidarh 2008-03-26T20:58:36Z This is part 1 in what will be a long series (ca. 30 parts written so far) about writing a small compiler in Ruby "bottom up", in other words starting with the code generator, rather than the more conventional approach of starting with the parser. The focus is not so much on Ruby as it is on how to build a code generator and how to implement low level features of a language in the simplest possible way.]]> 72627 2008-03-25T21:04:05Z 2008-03-26T20:58:36Z 11 0 570 1 http://www.dzone.com/links/images/thumbs/120x90/72627.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/urls_do_not_belong_in_the_views.html It's bothered me for some time to hardcode URLs in my views. It means that if I want to revise the linking structure, I may need to modify the views in a huge number of places. At the same time I don't like the thought of putting it in the model either. This post briefly look at alternatives. frameworks opinion ruby web 2.0 Tue, 25 Mar 2008 20:55:59 GMT http://www.dzone.com/links/72466.html vidarh 2008-03-25T20:55:59Z It's bothered me for some time to hardcode URLs in my views. It means that if I want to revise the linking structure, I may need to modify the views in a huge number of places. At the same time I don't like the thought of putting it in the model either. This post briefly look at alternatives.]]> 72466 2008-03-25T08:17:30Z 2008-03-25T20:55:59Z 14 0 703 0 http://www.dzone.com/links/images/thumbs/120x90/72466.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/why_rails_is_total_overkill_and_why_i_love_rack.html Rails is total overkill. It tries to do "everything" in a massive framework where major components are tightly intervowen. Smaller frameworks like Merb and Camping have already shown you don't NEED this. I argue you don't need a framework at all - you need highly cohesive, loosely coupled components. That is why I love Rack - it does one thing and does it well, and leave me to write applications, not learn frameworks. frameworks opinion ruby web 2.0 Mon, 24 Mar 2008 09:48:12 GMT http://www.dzone.com/links/72183.html vidarh 2008-03-24T09:48:12Z Rails is total overkill. It tries to do "everything" in a massive framework where major components are tightly intervowen. Smaller frameworks like Merb and Camping have already shown you don't NEED this. I argue you don't need a framework at all - you need highly cohesive, loosely coupled components. That is why I love Rack - it does one thing and does it well, and leave me to write applications, not learn frameworks.]]> 72183 2008-03-23T11:40:29Z 2008-03-24T09:48:12Z 8 0 1038 9 http://www.dzone.com/links/images/thumbs/120x90/72183.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/rack_middleware_adding_cache_headers.html Rack is an interface between web servers and Ruby web frameworks. This entry shows how to add cache headers to arbitrary Rack apps by plugging in a tiny Rack middleware class - it can rewrite headers from plain rack apps, Merb, Ramaze, Sinatra, Rails or any other framework with a Rack adapter. frameworks how-to ruby tools Sat, 22 Mar 2008 12:41:47 GMT http://www.dzone.com/links/72103.html vidarh 2008-03-22T12:41:47Z Rack is an interface between web servers and Ruby web frameworks. This entry shows how to add cache headers to arbitrary Rack apps by plugging in a tiny Rack middleware class - it can rewrite headers from plain rack apps, Merb, Ramaze, Sinatra, Rails or any other framework with a Rack adapter.]]> 72103 2008-03-22T12:41:47Z 1 0 21 0 http://www.dzone.com/links/images/thumbs/120x90/72103.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/web20_style_logo_reflection_with_ruby_and_cairo.html I keep trying to learn more about Cairo, and cheesy logo effects seems to be as good a way as any. This evening I was playing around with clip paths, and decided to use it to create some reflections. I wrote up this short how-to to explain what I did. how-to ruby web 2.0 web design Sat, 22 Mar 2008 02:13:10 GMT http://www.dzone.com/links/72057.html vidarh 2008-03-22T02:13:10Z I keep trying to learn more about Cairo, and cheesy logo effects seems to be as good a way as any. This evening I was playing around with clip paths, and decided to use it to create some reflections. I wrote up this short how-to to explain what I did.]]> 72057 2008-03-22T02:13:10Z 2 0 22 0 http://www.dzone.com/links/images/thumbs/120x90/72057.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/using_sequel_and_ruby_to_import_the_geonames_data.html A short howto on how to import the Geonames dataset into a database using Ruby and the Sequel ORM. The example uses Sqlite but can easily be adapter to MySQL or Postgres etc.. Even if you're not interested in Geonames it serves as a simple example of using Sequel model classes. database how-to ruby Fri, 21 Mar 2008 15:18:53 GMT http://www.dzone.com/links/72019.html vidarh 2008-03-21T15:18:53Z A short howto on how to import the Geonames dataset into a database using Ruby and the Sequel ORM. The example uses Sqlite but can easily be adapter to MySQL or Postgres etc.. Even if you're not interested in Geonames it serves as a simple example of using Sequel model classes.]]> 72019 2008-03-21T15:18:53Z 3 0 53 0 http://www.dzone.com/links/images/thumbs/120x90/72019.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif http://www.dzone.com/links/rss/draw_a_logo_with_gradients_with_ruby_and_cairo.html A short tutorial showing how to draw a logo with a gradient and simple drop shadow using Ruby and Cairo. how-to ruby web 2.0 web design Thu, 20 Mar 2008 22:59:54 GMT http://www.dzone.com/links/71924.html vidarh 2008-03-20T22:59:54Z A short tutorial showing how to draw a logo with a gradient and simple drop shadow using Ruby and Cairo.]]> 71924 2008-03-20T22:59:54Z 4 0 26 0 http://www.dzone.com/links/images/thumbs/120x90/71924.jpg vidarh http://www.dzone.com/links/images/avatars/279649.gif