8 ene 2008

Python

leyendo varios libros sobre Python me encontré esto (tomado del libro de Prentice-Hall core Python)

History of Python
Work on Python began in late 1989 by Guido van Rossum, then at CWI in the Netherlands, and eventually released for public distribution in early 1991. How did it all begin? Innovative languages are usually born from one of two motivations: a large well-funded research project or general frustration due to the lack of tools that were needed at the time to accomplish mundane and/or time-consuming tasks, many of which could be automated.
At the time, van Rossum was a researcher with considerable language design experience with the interpreted language ABC, also developed at CWI, but he was unsatisfied with its ability to be developed into something more. Some of the tools he envisioned were for performing general system administration tasks, so he also wanted access to the power of system calls that were available through the Amoeba distributed operating system. Although an Amoeba-specific language was given some thought, a generalized language made more sense, and late in 1989, the seeds of Python were sown.

Features of Python


Object-oriented
Object-oriented programming (OOP) adds another dimension to structured and procedural languages where data and logic are discrete elements of programming. OOP allows for associating specific behaviors, characteristics, and/or capabilities with the data that they execute on or are representative of. The object-oriented nature of Python was part of its design from the very beginning. Other OO scripting languages include SmallTalk, the original Xerox PARC language that started it all, and Netscape's JavaScript.

High-level
It seems that with every generation of languages, we move to a higher level. Assembly was a godsend for those who struggled with machine code, then came FORTRAN, C, and Pascal, all of which took computing to another plane and created the software development industry. These languages then evolved into the current compiled systems languages C++ and Java. And further still we climb, with powerful, system-accessible, interpreted scripting languages like Tcl, Perl, and Python. Each of these languages has higher-level data structures that reduce the "framework" development time which was once required. Useful types like Python's lists (resizeable arrays) and dictionaries (hash tables) are built into the language. Providing these crucial building blocks encourages their use and minimizes development time as well as code size, resulting in more readable code. Implementing them in C is complicated and often frustrating due to the necessities of using structures and pointers, not to mention repetitious if some forms of the same data structures require implementation for every large project. This initial setup is mitigated somewhat with C++ and its use of templates, but still involves work that may not be directly related to the application that needs to be developed.

Portable
Python is available on a wide variety of platforms


Easy-to-read
Conspicuously absent from the Python syntax are the usual symbols found in other languages for accessing variables, code block definition, and pattern-matching. These include: dollar signs ( $ ), semicolons ( ; ), tildes ( ~ ), etc. Without all these distractions, Python code is much more clearly defined and visible to the eyes. In addition, much to many programmers' dismay (and relief), Python does not give as much flexibility to write obfuscated code as compared to other languages, making it easier for others to understand your code faster and vice versa. Being easy-to-read usually leads to a language's being easy-to-learn, as we described above. We would even venture to claim that Python code is fairly understandable, even to a reader who has never seen a single line of Python before. Take a look at the examples in the next chapter, Getting Started, and let us know how well you fare.

Easy-to-maintain

Maintaining source code is part of the software development lifecycle. Your software is permanent until it is replaced or obsoleted, and in the meantime, it is more likely that your code will outlive you in your current position. Much of Python's success is that source code is fairly easy-to-maintain, dependent, of course, on size and complexity. However, this conclusion is not difficult to draw given that Python is easy-to-learn and easy-to-read. Another motivating advantage of Python is that upon reviewing a script you wrote six months ago, you are less likely to get lost or require pulling out a reference book to get reacquainted with your software.

A Memory Manager
The biggest pitfall with programming in C or C++ is that the responsibility of memory management is in the hands of the developer. Even if the application has very little to do with memory access, memory modification, and memory management, the programmer must still perform those duties, in addition to the original task at hand. This places an unnecessary burden and responsibility upon the developer and often provides an extended distraction.
Because memory management is performed by the Python interpreter, the application developer is able to steer clear of memory issues and focus on the immediate goal of just creating the application that was planned in the first place. This lead to fewer bugs, a more robust application, and shorter overall development time.


Algo de historia y de caracteristicas de Python el cual me parece un lenguaje interesante

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