Today. Generic Language g Technology (2IS15)

(1)

Generic Language Technology (2IS15)g g gy ( ) Domain Specific Language Design

Prof.dr. Mark van den Brand

Today

• Toolsfor software analysis and manipulationy

• Programming language independent(parametric)

• The story is from the IDE/PEperspective

• First a general overview, then introduction to specific technologies

/ Faculteit Wiskunde en Informatica 7-9-2011 PAGE 1

What …

• ... is a language?g g

• ... is a Programming Environment (PE)?

• ... is Generic Language Technology (GLT)?

• ... is a Program Generator?

• ... is a Programming Environment Generator?

What …

(2)

What is a language?

• A programming languageg g g g

• Assembler, Cobol, PL/I, C, C++, Java, C#, ...

A D i S ifi L (DSL)

• A Domain-Specific Language (DSL)

• SQL for queries

• BibTex for entries in a bibliographyBibTex for entries in a bibliography

• Euris for railroad emplacement safety

• Risla for financial products

• WebDSL for web pages

Aspects of a Language

• Syntaxy

• Textual/graphical form of declarations, statements, etc.

• Static Semantics

• Scope and type of variables, conversions, formal/actual parameters, etc.

• Queries: who calls who, who uses variable X, ..., ,

• Dynamic Semantics

• Program execution

• Tooling

What …

What is a Programming Environment

• A system that supports the development of

i d t

programs in order to:

• Increase productivity:

− Uniform user-interface (UI); integrated tools

− Increased interaction; early error detection

• Increase quality:

− Integrated version managementIntegrated version management

− Integrated testing

(3)

Classical PE

• Command line oriented:

• Text editor only − xemacs or vim

j

− gcc or javac

• Programs stored in files

• Complete recompilation after each changeComplete recompilation after each change • Late error detection

• Debugging requires recompilation with different options

Integrated PE (IPE)

• Integrated Development Environment (IDE)g ( )

• Specialized, syntax-directed, editor for each language • Common intermediate representation for all tools • Incremental processing (reusing results of previous

calculations) • One GUIOne GUI

• Early error detection − Syntax errors

− Undeclared variables

− Type errors in expressions

Functionality of an IDE

• Syntax-directed editing/highlighting, pretty printingy g g g g y g

• Typechecking

• Restructuring

• Versioning

• Executing, debugging, profiling T ti

• Testing

• Documenting

Examples of IDEs

• Eclipse: www.eclipse.orgg

• Integrated Development Environment (IDE) for Java

• Plug-in mechanism for extensions

MS Vi l St di d i ft / t di

• MS Visual Studio: msdn.microsoft.com/vstudio

(4)

What …

What is Generic Language Technology?

• Goal: Enable the easy creation of language-specific y g g tools and programming environments

• Separate language-specificaspects from generic

aspects aspects

• Approach:

• Find good, reusable, solutions for generic aspectsd good, eusab e, so ut o s o ge e c aspects

• Find ways to define language-specific aspects

• Find ways to generate tools from language-specific d fi iti

definitions

Generic Aspects

• User-interface

• Text editor

• Program storage

• Documentation

Defining Language Aspects

• Syntaxy

• Lexical and context-free grammar

• Static semantics

• Ad hoc?

• Dynamic semantics

• Ad hoc?

(5)

From Definition to Tool

• Syntaxy

• Scanner and parser generation

• Static semantics

• ???

• Dynamic semantics

• ???

Examples of Generic IDEs

• Eclipse IMP: http://eclipse-imp.sourceforge.net/imp.html

• A framework for Generic Integrated Development Environments (IDE)

• The goal of the Eclipse IMP is to provide an extensibleThe goal of the Eclipse IMP is to provide an extensible platform for the development of high-quality, fully-featured, language-specific IDE's in Eclipse

• Spoofax/IMP:Spoofax/IMP: http://strategoxt.org/Spoofaxhttp://strategoxt org/Spoofax

• Rascal: http://www.rascal-mpl.org/

What …

What is Program Generator?

Definition of problem P

Generator

(6)

Examples of Program Generators (1)

• Regular expression matching:g g

• Problem: recognize regular expressions R₁, ..., R_nin a text

• Generates: finite automaton

• Web sites

• Problem: create uniform web site for set of HTML pagesp g

• Generate: HTML code with standard layout and site map

Examples of Program Generators (2)

• Generate bibliographic entries; inputg

@article{BJKO00, author = {Brand, {M.G.J. van den} and Jong, {H.A. de} and P. Klint and P. Olivier}, title = {{E}fficient {A}nnotated {T}erms},

journal = {Software, Practice \& Experience}, year = {2000},

pages = {259--291},

p g { },

volume = {30}} generates:

M G J van den Brand H A de Jong P Klint and P A Olivier Efficient M.G.J. van den Brand, H.A. de Jong, P. Klint and P.A. Olivier, Efficient Annotated Terms, Software, Practice & Experience, 30(3):259―291, 2000

Examples of Program Genators (3)

• Compiler:

• Input: Java program

• Generates: JVM code C

• C preprocessor:

• Input C program with #include, #definedirectives

• Generates C program with directives replacedGenerates C program with directives replaced

Program Generators (summary)

• Problem description is specific and is usually written y in a Domain-Specific Language (DSL)

• Generator contains generic algorithms and information about application domain information about application domain.

• A PG isolates a problem description from its implementation p easier to switch to other implementation methods.

• Improvements/optimizations in the generator are good for all generated programs

(7)

What …

What is Programming Environment

Generator (PEG)?

• A PEG is a program generator applied in the p g g pp domain of programming environments

• Input: description of a desired language L

• Output: (parts of) a dedicated Lenvironment

• Advantages:

U if i t f diff t l

• Uniform interface across different languages

• Generator contains generic, re-usable, implementation knowledge

• Disadvantage: some UI optimizations are hard

Programming Environment Generator

Formal definition of language L

Generator Generator

PEG = collection of program generators

Definition of L static semantics Definition of L syntax Definition of L dynamic semantics

Parser Typechecker Evaluator Generator

yp

(8)

Programming Environment Generator

• PEG allows definition of (small) (domain specific) ( ) ( ) languages

• PEG = language workbench

Summary

• Evolution from traditional PE via IDE to language g g workbenches

• How to describe the syntax and semantics of a (small) (domain specific) language

(small) (domain specific) language

• Questions so far?Questions so far?