Tutorial by Examples: re

To temporarily mark a file as ignored (pass file as parameter to alias) - type: unwatch = update-index --assume-unchanged To start tracking file again - type: watch = update-index --no-assume-unchanged To list all files that has been temporarily ignored - type: unwatched = "!git ls-fil...

Users of homebrew can install gradle by running brew install gradle

Sometimes you need rewrite history with a rebase, but git push complains about doing so because you rewrote history. This can be solved with a git push --force, but consider git push --force-with-lease, indicating that you want the push to fail if the local remote-tracking branch differs from the b...

Before the C compiler starts compiling a source code file, the file is processed in a preprocessing phase. This phase can be done by a separate program or be completely integrated in one executable. In any case, it is invoked automatically by the compiler before compilation proper begins. The prepro...

Sometimes it's necessary to convert a Discriminated Union to and from a string: module UnionConversion open Microsoft.FSharp.Reflection let toString (x: 'a) = match FSharpValue.GetUnionFields(x, typeof<'a>) with | case, _ -> case.Name let fromStri...

Given the text: foo: bar I would like to replace anything following "foo: " with "baz", but I want to keep "foo: ". This could be done with a capturing group like this: s/(foo: ).*/$1baz/ Which results in the text: foo: baz Example 1 or we could use \K,...

The order of keys in Python dictionaries is arbitrary: they are not governed by the order in which you add them. For example: >>> d = {'foo': 5, 'bar': 6} >>> print(d) {'foo': 5, 'bar': 6} >>> d['baz'] = 7 >>> print(a) {'baz': 7, 'foo': 5, 'bar': 6} >&g...

This example comes from the official document. Suppose you have a python application using redis as backend. After writing Dockerfile, create a docker-compose.yml file like this: version: '2' services: web: build: . ports: - "5000:5000" volumes: - .:/code ...

You can add wildcards in string resources and populate them at runtime: Edit strings.xml <string name="my_string">This is %1$s</string> Format string as needed String fun = "fun"; context.getString(R.string.my_string, fun);

The return statement can be used to exit function and subroutine. Unlike many other programming languages it is not used to set the return value. real function f(x) real, intent(in) :: x integer :: i f = x do i = 1, 10 f = sqrt(f) - 1.0 if (f < 0) then f = -1...

Floating point numbers of type real cannot have any real value. They can represent real numbers up to certain amount of decimal digits. FORTRAN 77 guaranteed two floating point types and more recent standards guarantee at least two real types. Real variables may be declared as real x double prec...

This example shows how to create a simple notification that starts an application when the user clicks it. Specify the notification's content: NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this) .setSmallIcon(R.drawable.ic_launcher) // notification icon .se...

iex(1)> a = 10 10 iex(2)> b = 20 20 iex(3)> a + b 30 You can get a specific row passing the index of the row: iex(4)> v(3) 30 You can also specify an index relative to the current row: iex(5)> v(-1) # Retrieves value of row (5-1) -> 4 30 iex(6)> v(-5) # Retrieves...

There are a couple ways you can reverse a string to make it backwards. StringBuilder/StringBuffer: String code = "code"; System.out.println(code); StringBuilder sb = new StringBuilder(code); code = sb.reverse().toString(); System.out.println(code); Char array: S...

All these are shell commands. docker-machine env to get the current default docker-machine configuration eval $(docker-machine env) to get the current docker-machine configuration and set the current shell environment up to use this docker-machine with . If your shell is set up to use a proxy, yo...

The following (trivial) example function simply returns the constant INT value 12. DELIMITER || CREATE FUNCTION functionname() RETURNS INT BEGIN RETURN 12; END; || DELIMITER ; The first line defines what the delimiter character(DELIMITER ||) is to be changed to, this is needed to be s...

public async Task<Product> GetProductAsync(string productId) { using (_db) { return await _db.QueryFirstOrDefaultAsync<Product>("usp_GetProduct", new { id = productId }, commandType: CommandType.StoredProcedure); } }

prop_evenNumberPlusOneIsOdd :: Integer -> Property prop_evenNumberPlusOneIsOdd x = even x ==> odd (x + 1) If you want to check that a property holds given that a precondition holds, you can use the ==> operator. Note that if it's very unlikely for arbitrary inputs to match the precondit...

To make express web application modular use router factories: Module: // greet.js const express = require('express'); module.exports = function(options = {}) { // Router factory const router = express.Router(); router.get('/greet', (req, res, next) => { res.end(options....

You can use the reversed function which returns an iterator to the reversed list: In [3]: rev = reversed(numbers) In [4]: rev Out[4]: [9, 8, 7, 6, 5, 4, 3, 2, 1] Note that the list "numbers" remains unchanged by this operation, and remains in the same order it was originally. To r...