The following embeds an untrusted web page with all restrictions enabled
<iframe sandbox src="http://example.com/"></iframe>
To allow the page to run scripts and submit forms, add allow-scripts and allow-forms to the sandbox attribute.
<iframe sandbox="allow-script...
To create a build target producing an executable, one should use the add_executable command:
add_executable(my_exe
main.cpp
utilities.cpp)
This creates a build target, e.g. make my_exe for GNU make, with the appropriate invocations of the configured compiler to pr...
ListView - A core component designed for efficient display of vertically scrolling lists of changing data. The minimal API is to create a ListView.DataSource, populate it with a simple array of data blobs, and instantiate a ListView component with that data source and a renderRow callback which take...
Drag 1 textbox and 1 button
Double click the button1 and you will be transferred to the Button1_Click event
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
End Sub
End Class
Type the name of the object that you want to target, ...
Using sw As New System.IO.StreamWriter("path\to\file.txt")
sw.WriteLine("Hello world")
End Using
The use of a Using block is recommended good practice when using an object that Implements IDisposable
def str = 'old'
def interpolated = "I am the ${str} value"
assert interpolated == 'I am the old value'
str = 'new'
assert interpolated == 'I am the old value'
We can have lazy interpolation in Strings. This is different than normal interpolation as the GString can potentially have different values, depending on the closure, whenever it is converted into a String.
def str = 'old'
def interpolated = "I am the ${ -> str} value"
assert interpo...
Example from the standard library (core.clj:807):
(defmacro and
"Evaluates exprs one at a time, from left to right. If a form
returns logical false (nil or false), and returns that value and
doesn't evaluate any of the other expressions, otherwise it returns
the value of the last e...
section .data
msg db "Hello world!",10 ; 10 is the ASCII code for a new line (LF)
section .text
global _start
_start:
mov rax, 1
mov rdi, 1
mov rsi, msg
mov rdx, 13
syscall
mov rax, 60
mov rdi, 0
syscall
If you want to e...
Using GNU grep
grep -r 'pattern' <directory path>
To also list line numbers of matches use -n option
grep -rn 'pattern' <directory path>
To search only files with particular glob pattern
grep --include='*.txt' -r 'pattern' <directory path>
Exclude file patterns or direc...
Environments in R can be explicitly call and named. Variables can be explicitly assigned and call to or from those environments.
A commonly created environment is one which encloses package:base or a subenvironment within package:base.
e1 <- new.env(parent = baseenv())
e2 <- new.env(parent ...
The on.exit() function is handy for variable clean up if global variables must be assigned.
Some parameters, especially those for graphics, can only be set globally. This small function is common when creating more specialized plots.
new_plot <- function(...) {
old_pars <- par(m...
Thread.sleep causes the current thread to suspend execution for a specified period. This is an efficient means of making processor time available to the other threads of an application or other applications that might be running on a computer system. There are two overloaded sleep methods in the Thr...
CSS resets take separate approaches to browser defaults. Eric Meyer’s Reset CSS has been around for a while. His approach nullifies many of the browser elements that have been known to cause problems right off the back. The following is from his version (v2.0 | 20110126) CSS Reset.
html, body, di...
To declare exposed ports from a Dockerfile use the EXPOSE instruction:
EXPOSE 8080 8082
Exposed ports setting can be overridden from the Docker commandline but it is a good practice to explicitly set them in the Dockerfile as it helps understand what an application does.
It is possible to save a Docker container's filesystem contents to a tarball archive file. This is useful in a pinch for moving container filesystems to different hosts, for example if a database container has important changes and it isn't otherwise possible to replicate those changes elsewhere. Pl...
