Installing libffi-dev and re-installing python3.7 fixed the problem for me. to cleanly build py 3.7 libffi-dev is required or else later stuff will fail If using RHEL/Fedora: yum install libffi-devel or sudo dnf install libffi-devel If using Debian/Ubuntu: sudo apt-get install libffi-dev
change public class LinqHelper to public static class LinqHelper Following points need to be considered when creating an extension method: The class which defines an extension method must be non-generic, static and non-nested Every extension method must be a static method The first parameter of the extension method should use the this keyword.
Check if you are referencing an assembly which in turn referencing an old version of unity. For example let’s say you have an assembly called ServiceLocator.dll which needs an old version of Unity assembly, now when you reference the ServiceLocator you should provide it with the old version of Unity, and that makes the problem. … Read more
The gcc compiler is not in your $PATH. It means either you dont have gcc installed or it’s not in your $PATH variable. To install gcc use this: (run as root) Redhat base: yum groupinstall “Development Tools” Debian base: apt-get install build-essential openSUSE base: zypper install –type pattern devel_basis Alpine: apk add build-base
You must understand the difference between a class and an instance of that class. If you see a car on the street, you know immediately that it’s a car even if you can’t see which model or type. This is because you compare what you see with the class “car”. The class contains which is … Read more
You need to use this line of code to resolve your problem: __block Person *aPerson = nil; For more details, please refer to this tutorial: Blocks and Variables
The way to think about this is to “think like a compiler”. Imagine you are writing a compiler. And you see code like this. // file: A.h class A { B _b; }; // file: B.h class B { A _a; }; // file main.cc #include “A.h” #include “B.h” int main(…) { A a; } … Read more
Originally from Overv @ reddit.
0. Is there any difference between these errors? Not really. “Cannot find symbol”, “Cannot resolve symbol” and “Symbol not found” all mean the same thing. (Different Java compilers are written by different people, and different people use different phraseology to say the same thing.) 1. What does a “Cannot find symbol” error mean? Firstly, it … Read more
The .NET Assembly loader: is unable to find 1.2.0.203 but did find a 1.2.0.200 This assembly does not match what was requested and therefore you get this error. In simple words, it can’t find the assembly that was referenced. Make sure it can find the right assembly by putting it in the GAC or in … Read more