Language Implementation Methods

David Woolbright

Interpretation

• Interpretation occurs when the code that represents a program is read and causes an action or change in state of the executing machine.

• Interpretation can occur in hardware or software

Implementation of Languages

There are three general methods for implementing a language

Method 1: Compilation – The source program is translated into machine code (0’s and 1’s) which is interpreted by hardware

- Slow translation

- Fast execution

Compilation Process

(Sebesta Diagram)

Pure Interpretation

Method 2: Pure Interpretation – The source code is unchanged. An interpreter program executes reading your source as data to determine how to “execute” your program

- Slow execution

- Very flexible

Pure Interpretation (Sebesta Diagram)

Hybrid System

Method 3: Hybrid System - The source code is partially translated to an intermediate format. This intermediate code is input to an interpreter.

– Small translation cost

– Medium execution speed

Hybrid System(Sebesta Diagram)

- Small translation cost- Medium execution speed