autolisp programming

The process of The AUTOLISP program is controlled by flow control functions. 1. Branch Structure (1) (cond (test expression 1 Result Expression 1) [(test expression 2 Result Expression 2)]...) [Example] 1 (setq n( cond(( Note: This function is similar to the switch statement in C language. The last test expression "t (or t)" is equivalent to "default" and refers to other cases. This test expression is also missing. Different from the C language switch

Rule 1: The parentheses form the expression, the left and right brackets "(" and ")" must be paired, relative, and the internal string double quotes "" "and" "" should also be paired.Rule 2: Expression format: (function name operator operator)* Operation functions include function functions and custom functions.* Operators (Independent variables) include: integers (integer), such as 8,-17,500,,9999; Real (real), such as 8.5,-17.456; Strings (string), such as: "AutoCAD", "123";

How do I get a layer name for straight and multi-line lines in CAD graphics files with AutoLisp? Use (CDR (Assoc 8 (Entget (Entsel))) to get the layer name of the line and other entities. The program you want is to point to a line, get the layer name of the line, and then change the line width of all the lines in that layer to a value. What I want now is the step of "point to line, get the layer name". (Setq Lyname (CDR (Assoc 8 (Entget (Entsel))))

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the Tiobe ranking is still 100, in 2016 years a year from 169th to 137. So who will spend the annual programming language of 2017? We predict that C + +, Swift, Julia and Typescript will all be strong contenders for this position. TOP20 List of programming languages The following is the 第21-50位 programming language, ranked as follows: Top 10

I have been engaged in pythonWeb development for a year. Now I am confused. I mainly work on curd, that is, how to obtain data, and then present it to the front-end page. The framework uses django, optimization means adding memecache. Pay attention to this when querying the database. Currently, there are a lot of tangled issues: 1: the programming of process threads, how to use it in practice 2: network programmin