Colon Class § 5.3: Dynamic language

Lesson five language Small Talk (3)

5.3 Dynamic Language--a script language flying in colorful clothes

So where the reason of the world, want to move on the static, static on the move--"Cai-hair micro-theory"

Keywords: dynamic language, static language, scripting language

Summary: A brief talk on dynamic language

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• Programs are services for end users, and scripts are for programmers

• The idea of a dynamic language is to optimize people's time rather than machine time

• To the static language of the helmet Dai, prepare the horse Shame, dynamic language has been floating, sword shot

• When the script language in the dynamic language of color clothing, the former humble caterpillar will feather into a dish, began to fly in the eyes of the people chasing

？ Questions

• What is the difference between a script and a program?

• What are the features of scripting languages? Why is it suitable for adhesion language?

• What are the characteristics of dynamic languages? What is the difference between it and the scripting language?

• Can dynamic languages also be used for large-scale application development?

• Will the dynamic language eventually replace the static language?

: Explain

Exclamation-Mark impatient to ask: "Now can talk about dynamic language?" ”

Colon speech: "Once upon a time, dynamic language is only to accompany the Prince reading role, when their name is ' scripting language '." Recently, but the rapid rise, as if there is a rival to the static language. ”

The question mark cannot help asking: "Is the dynamic language and the scripting language the same thing?" ”

The concept of scripting language is more explicit than the ambiguity of dynamic language definition. "Colon avoidance gives the answer directly," The script's reference is to distinguish it from the general program. The inventor of Perl, Larry Wall, deserves to be a linguist, and there's a wonderful saying: ' A script is what you give the actors, and a program is what you give the audience '. The script is for the actor, the program is for the audience to see. This is the meaning of pun--program ' program ' and ' procedure '. ”

The full stop comprehends its meaning: "The actors here refer to the programmer, the audience refers to the user." In other words, the program is for the end-user service, and the script is for the programmer. ”

"Positive solution!" The most common form of the "colon affirmative" script is shell script (shell scripts), also known as batch files (batch file) in non-UNIX-class operating systems. ”

"Batch files are familiar, shell scripts sound strange." The comma muttered.

"That's because you grew up in the world of windows and didn't listen to the dialect of Unix. "The colon nail reason," the operating system's core is called the kernel (kernel), which is not directly interacting with the user for security reasons, so it wraps up a shell (the shell), the command-line interpreter (command line interpreter) that people often say. A shell script is a script that runs on the shell, extending commands that can be executed under the command line. It is primarily a combination of built-in (built-in) commands, for System program scheduling, is the system administrator's necessary weapons. Since then, shell scripts have evolved to be used for application scheduling, connectivity, debugging, and so on, to become bonding (glue) languages. ”