ada

问题 I have a package called Statements with an abstract type called Statement and an abstract function called execute(). In another package I have a type CompoundStatement which is a type Statement and it implements the execute() function. I have a function called createStatement(). It's purpose is to evaluate a token of type Unbounded_String and determine what keyword it contains. Then based on this keyword it will generate an access type based on this keyword. So far so good. But what I can't

问题 I am trying to write an Ada equivalent to the split() method in Java or C++. I am to intake a string and an integer and output two seperate string values. For example: split of "hello" and 2 would return: "The first part is he and the second part is llo" The code I have is as follows: -- split.adb splits an input string about a specified position. -- -- Input: Astring, a string, -- Pos, an integer. -- Precondition: pos is in Astring'Range. -- Output: The substrings Astring(Astring'First..Pos)

问题 How can I use threads in Ada95? What functions can I use to create, destroy, stop and start them? How can I use semaphores in this language? 回答1: Ada's terminology for a thread is a "task". Ada doesn't have semaphores (as such) built directly into the language, but Googling for something like "Ada semaphore" should turn up a fair number of hits. AdaPower.com, in particular, has quite a bit about concurrent programming in Ada (and, for that matter, almost all kinds of programming in Ada). 回答2:

问题 I downloaded the Netbeans plugin for programming with Ada. However, I dunno how to link the Eclipse to the Ada platform library. What should link to the IDE ? lib,etc,bin ? I dunno what what to do. Any help is appreciated. 回答1: After installing the Ada plugin modules in NetBeans, use File > New Project to create a new Ada project. In the New Ada Application dialog, click Manage to select your installed Ada compiler. 回答2: I don't know about Netbeans or Eclipse, but this might be applicable?

问题 I installed Ada and AWS on a Macbook for the first time tonight. Everything seemed successful with the installation, but I'm getting the feeling that AWS didn't install to the right directory. GNAT is in /usr/local/gnat. The AWS makefile.conf said, AWS will be installed under $(prefix). Update this variable to point to the install directory. By default, it is set to the current GNAT root directory to have AWS project files automatically available. So I didn't change the target. But when I try

问题 I have the following code for network protocol implementation. As the protocol is big endian, I wanted to use the Bit_Order attribute and High_Order_First value but it seems I made a mistake. With Ada.Unchecked_Conversion; with Ada.Text_IO; use Ada.Text_IO; with System; use System; procedure Bit_Extraction is type Byte is range 0 .. (2**8)-1 with Size => 8; type Command is (Read_Coils, Read_Discrete_Inputs ) with Size => 7; for Command use (Read_Coils => 1, Read_Discrete_Inputs => 4); type

问题 I have a function which averages a certain numeric value from an array of records. This value is either a natural or an enumerated type delta. I have it summing up the values correctly but my question is this: how do I get the length of an array into a generic type, so that it can divide both integers and delta type numbers? 回答1: On your array-of-records use the 'Length attribute; this has the advantage of always working even if your bounds are somewhat odd, like -18..3, or an enumeration,

问题 I'm writing a tool to parse Ada source file with the grammar provided in 2005 Annex P. With following piece of code, I know ["03C0"] stands for "greek letter Pi", but is it a legal variable name? 01 package Ada.Numerics is 02 Pi : constant := 3.14159_26535_89793_23846_26433_83279_50288_41971_69399_37511; 03 ["03C0"] : constant := Pi; 04 e : constant := 2.71828_18284_59045_23536_02874_71352_66249_77572_47093_69996; 05 end Ada.Numerics; When using the grammar to parse line 03, I currently come

问题 I'm very new to Ada, and I'm trying to do some simple work with some text. All I want to do is read in a file, and strip out anything that isn't a letter, space, or new line. so removing all the punctuation and numbers. In other languages I would just create a simple [^a-zA-Z] regular expression, look at each character and delete it if it fit the RegEx, but I can't seem to find any documentation on RegEx's in Ada. So, are there RegEx's in Ada? If not, what's the best way for me to go about

问题 Are there any freely available Ada plugins eclipse. Eclipse is my main IDE and I occasionally need to read and modify some Ada, having it all in the one IDE would be ideal. 回答1: For Eclipse, AdaCore distributes and maintains the GNATBench plug-in, though I've never personally used it. I believe it is not GNAT specific, so it may still be of value even if you're using a different compiler--but I could be wrong on that :-) If you're using the GNAT Ada compilation system, you've got a fully Ada