First steps

Requirements

• Have at least a basic knowledge of EMF (Eclipse Modeling Framework).
• Have installed ALE Compiler.

Objectives

• Compile an ALE project to Java.
• Execute a program using the compiled language.

Get the HelloWorld example from ALE

ALE provides an Hello world! project template:

1. File > New > Example...
2. EcoreTools ALE Examples > Hello world!
3. Select helloworld
4. Finish

After a few seconds a new project called helloworld should be created in your workspace. This project defines a simple HelloWorld EClass able to print “Hello world!”. The content of the project is presented below.

What we have inside

For more details of the language’s architecture, see ALE first steps.

Compile!

At this point you are able to interpret Helloworld programs using the ALE interpreter.

Compilation using the Eclipse IDE

1. Create an Eclipse Plugin-in Project named ‘helloworld.interpreter’
2. Create src/helloworld.dsl in this project, with the following content:

syntax=platform:/resource/helloworld/model/helloworld.ecore
behavior=platform:/resource/helloworld/model/helloworld.ale
compilationType=interpreter

1. Create a genmodel file for helloworld.ecore
2. Open META-INF/MANIFEST.MF, and on the Dependencies list, add org.eclipse.emf.ecore, helloworld, and org.eclipse.emf.ecoretools.ale.compiler.lib on the project’s required plugins.
3. Right click on the dsl file and select ALE > Generate Ale Implementation
4. Right click on the newly created interpreter-comp directory and select **Build Path > Use as Source Folder

You have generated a compiled version of the helloworld language following the Interpreter implementation pattern.

By substituting interpreter by visitor, switch or revisitor in the steps above, you can freely compile your language to another implementation pattern.

Compilation with Maven

Prerequisite: We do not cover the details of the integration of you project using maven but several example of ALE language with a maven integration can be found in the ale compiler github repository.

Once your language integrated with maven, the automated compilation using the alecompiler-maven-plugin can be integrated by adding the following definition in your language’s pom.xml:

<build>
    <sourceDirectory>PATTERN-comp</sourceDirectory>
    <plugins>
        <plugin>
            <groupId>org.eclipse.emf.ecoretools.ale.compiler</groupId>
            <artifactId>alecompiler-maven-plugin</artifactId>
            <version>1.0.0-SNAPSHOT</version>
            <executions>
                <execution>
                    <phase>generate-sources</phase>
                    <goals>
                        <goal>ale-dsl-compile</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <dslFile>${project.basedir}/src/LANGUAGE.dsl</dslFile>
            </configuration>
        </plugin>
    </plugins>
</build>