Thoughts on agile software development
FreshMarker 3.0.0 will introduce an ahead-of-time (AOT) and just-in-time (JIT) template compiler. This first post in a three-part series explains what changes under the hood, what you gain, and what you give up compared to the classic interpreter.
While designing a new feature, I once again stumbled upon a feature of the template language that I haven’t liked for a long time. The syntax of the directives is modeled after HTML elements, not XML elements. As long as you don’t want to change the syntax of the template language, this isn’t a problem. But if you have a great idea for a new feature, you’re in for a world of trouble.
When replicating the concepts of another template engine, there are always moments when you put off working on a particular concept. This rarely has anything to do with the complexity of the concept itself, but often stems from a personal aversion. For FreshMarker, this has meant that some concepts have been implemented late or completely reworked. Some concepts are still awaiting implementation. One of these concepts is the parameters of the nested directive, which will be implemented for FreshMarker 2.7.0.
Vor vier Jahren begann das Abenteuer FreshMarker mit dem Blog-Beitrag „FreshMarker, eine frische Template Engine für Java“. Was als akademisches Experiment startete, hat sich inzwischen zu einer vielseitigen und stabilen Template Engine entwickelt. Mit Version 2.5.0 und insgesamt 87 Blog-Beiträgen, die verschiedenste Aspekte beleuchten, ist nun der richtige Zeitpunkt für ein Resümee.
An important component of the FreshMarker template engine is the built-in expression language. The expression language is used to utilize not only variables but also complex expressions in directives and interpolations. When evaluating other expression languages for customer projects, sometimes I am interested in integrating some findings into the FreshMarker expression language.
Whitespace in a template engine like FreshMarker’s is fundamentally different from the rest of the characters outside of it’s language constructs. A considerable amount of whitespace and line breaks are only used to ensure that the structure of the template remains comprehensible to the author.
When updating some libraries that use FreshMarker, I was a bit surprised. The Hamcrest Matcher Generator library was still using Freemarker and also the library has never been published on Maven Central. Two things that should be fixed as soon as possible.
Nothing is so good that it can’t be reworked. The switch directive in FreshMarker differed from the FreeMarker variant quite early on. FreshMarker’s switch directive does not have a fall-through mechanism. This mechanism is a legacy of the C language family, whose switch statements with break also found their way into the template syntax. Since the end of 2024, FreeMarker now also has a new switch directive. How can this be incorporated into FreshMarker?
Some time ago I had the pleasure of giving a talk about FreshMarker at the Java User Group Bielefeld. At this event, the question arose as to why FreshMarker does not have an include directive like FreeMarker. The include directive can be used in FreeMarker to insert additional content into templates.
One of the fundamental design decisions for FreshMarker is always the question of whether a feature is actually needed or whether pre-processing the data can solve the problem. This is always a delicate balancing act, because any unnecessary pre-processing casts a shadow on the attractiveness of the template engine. It’s always a question of whether … Read more