Understanding Compilers, Interpreters, and Language Translators
What is a Metacompiler and What Are Some Examples?
A metacompiler is a program that receives the specification of a language as input. It then generates a compiler for that language as output. The development of metacompilers faces the difficulty of uniting the code generation part with the analysis.
What is a Translator?
A translator is a program that translates or converts a text or program written in a source language into a text or program in a destination language, providing error messages if possible.
What is the Function of a Language Translator?
The function of a language translator is to convert text from one language to another. For example, a translator from English to Spanish.
How Does a Compiler Work?
A compiler is a translator that takes a sentence in a formal language as input and produces an executable file as output. In essence, it performs a high-level translation to machine code.
How Does an Interpreter Work?
An interpreter is similar to a compiler, except that the output is an execution. The input program is interpreted and executed simultaneously.
What are Pseudo-Interpreted Languages?
These are languages in which the source program goes through a pseudo-compiler that generates a pseudo-executable. This pseudo-executable is then processed by an execution engine. This approach offers the advantage of portability, as you only need the runtime on any machine to run any pseudo-executable.
How Does a Preprocessor Work?
A preprocessor modifies the source program before the actual compilation. It makes use of macros and directives.
What is the Purpose of a Command Interpreter?
A command interpreter translates simple sentences into calls for library programs. They are especially used by operating systems, such as the shell of DOS or UNIX. They trigger the execution of programs that can be found resident in memory or on disk.
What is the Purpose of Assemblers and Macro-Assemblers?
- Assembler: A simple compiler in which the source language has a simple structure that allows for translating a source sentence to a machine code instruction. The language used is called assembly language and has a one-to-one correspondence between its instructions and machine code.
- Macro-Assembler: Macro-assemblers usually translate into several machine instructions. Essentially, a macro-assembler is an assembler with a preprocessor.
What is the Difference Between an Assembler and a Macro-Assembler?
- Assembler: One-to-one correspondence between instructions and machine code.
- Macro-Assembler: Usually translates into several machine instructions.
What is the Function of Source-to-Source Converters?
Source-to-source converters transform a higher-level language into another high-level language, enhancing portability.
What is a Cross Compiler?
A cross compiler generates code to run on a different machine. They are used in the development phase of new computers.
What are the Three Functions of a Computer?
Compile, link, and run.
What is an OBJ File?
An OBJ file has a record structure, with records of different lengths. Some records contain machine code, while others contain information. It also includes information on external objects.
What is a Compilation Pass?
A compilation pass refers to the number of times the source program is read. In some situations, reading the source file once is not enough for compilation.
What is Incremental Compilation?
Incremental compilation is a method where, if errors are discovered after compiling a program, only the changes are recompiled instead of correcting the source program and recompiling it completely. Ideally, only the parts containing errors are recompiled, and the generated code is carefully reinserted into the OBJ generated when errors were found.