Haskell function patterns 'otherwise' -

-

Is there any way that I can create a function with different definitions for different methods, including the < SomeFunc (pattern2) = def2 someFunc (& lt; otherwise / all other possible values ​​& gt;) = def3

Code>

Or if this is not possible, how can it be obtained?

Thanks in advance!

Best, Skyfather

You can use the wildcard match _ : 

  is just :: probably one - & gt; Bull - Here we do not care what is inside just `Just '(bus _) = true - here we do not care what this is, this is not right, so' returned 'is wrong _ = wrong   
 For clarification, the pattern is tried in the order defined by you, so the above mentioned task is  not   
  isJust _ = Is false (only _) = true   
 because the  _  pattern is the first match. What the compiler is actually doing is turning it internally into a case statement, so the first task  
  would be required x = x = x's case x - & gt; True _ - & gt; False   
 And as we know from every other programming language, which is in existence, case statement is tried.

Comments

Post a Comment

Popular posts from this blog

java - ImportError: No module named py4j.java_gateway -

-
I'm trying to call the Python using the Java program py4j . I've been installing the plug-in Eclipse and test name Piidvi project. I'm trying to execute the following part of the code found on py4j webpage: Import from py4j.java_gateway to JavaGateway, java_import gateway = JavaGateway () jvm = gateway.jvm java_import (jvm, '' Org.eclipse Kkorkrisorsej. * ") Vrkspes_rut = Jvankresourkesplginkgetvrkspas (). GetRoot (Gateway .help (workspace_root, '* Projects *') project_names = [project.getName () (for projects workpace_root.getProjects))] print (Projekt_nam) But I There is an error in import. I have checked that the P4JJ is present in the Jar Eclipse plugin directory. Can anyone help please? I had to install the py4j application
Read more

python - Receiving "KeyError" after decoding json result from url -

-
I am new to Python I am trying to parse JSON result from a URL. Basically, I was using the following: response = urllib.request.urlopen (url) json_obj = json.load (response) It should be a stroke "str 'not' bytes' in the lines of a given" JSON object, so after searching on the StackoverView Flo, I decode the response in this way: F = urllib.request.urlopen (Url) charset = f.info (). Get_param ('charset', 'utf8') data = f.read () decoded = json.loads (data.decode (charset)) If I print "decode" I is as follows: { 'link': { 'summary data': 'https: // localhost / piwebapi / streams / p0_7qHaW4UHU-RlCaz8tpasAAQAAAAU0hJTExNQU42NDIwXFNJTlVTT0lE / summary' 'value': 'https: // localhost / Piwebapi / streams / P0_7qHaW4UHU-RlCaz8tpasAAQAAAAU0hJTExNQU42NDIwXFNJTlVTT0lE / price ',' InterpolatedData ':' https: // localhost / Piwebapi / streams / P0_7qHaW4UHU-RlCaz8tpasAAQAAAAU0hJTE...
Read more

C++ Array Type Not Assignable in Copy Constructor -

-
I have a simple class that represents the triangle, which consists of three arrays square triangle {public: double x [3]; Double y [3]; Unsigned four colors [3]; }; I want to create objects in this square on the heap, then pass on those functions which will use the value from the array. Since I am in these items, I need to make a deep copy to make a copy. Triangle (const triangle and obj) {X = new double [3]; Y = new double [3]; Color = new unsigned char [3]; For (int i = 0; i I keep the following error: "Error: array type 'double [3]' is not assignable for each of the three arrays. I am taking the same view as discussion, and I do not know why I am unable to create a new array. The answer is also the same approach. Does anyone have any insights? Looks like I'm really stupid. I'm taking the same approach as discussed in this video. In the video, you can see that he started the array Read on the member-preliminary list and how it is dif...
Read more