Tutorial by Examples: e

Returns the value of any OS environment variable. MESSAGE OS-GETENV ("OS") VIEW-AS ALERT-BOX. On a Windows machine: MESSAGE OS-GETENV ("SHELL") VIEW-AS ALERT-BOX. Result on a Linux machine with Bash as current shell: ┌────── Message ───────┐ ...

Deletes a file, or a file-tree. As with many other OS-* utilities, you have to check status in OS-ERROR. OS-DELETE file-or-dir-to-delete [ RECURSIVE ] Delete the entire /tmp/dir tree: OS-DELETE VALUE("/tmp/dir") RECURSIVE. Delete the file called c:\dir\file.txt OS-DELETE VALUE...

Creates a directory, status is in OS-ERROR OS-CREATE-DIR directory Create a directory called /usr/local/appData OS-CREATE-DIR VALUE("/usr/local/appData").

Append one file to another. Status is checked in OS-ERROR OS-APPEND source target Appends targetfile.txt with sourcefile.txt: OS-APPEND VALUE("sourcefile.txt") VALUE("targetfile.txt").

Rename a file or directory. Status is in OS-ERROR. Can also be used to move files (or move and rename). OS-RENAME oldname newname Rename /tmp/old-name to /tmp/new-name: OS-RENAME VALUE("/tmp/old-name") VALUE("/tmp/new-name"). Move file c:\temp\old.txt to c:\new-dir\old....

Returns a list of all drives on a system. MESSAGE OS-DRIVES VIEW-AS ALERT-BOX. Result with four drives, C through F: On Linux the list will simply be empty as there by definitions are no "drives" connected. Listing directories is done in another way (INPUT FROM OS-DIR)

Client metrics cover the traffic between the client and the Varnish cache. sess_conn - Cumulative number of connections. client_req - Cumulative number of client requests. sess_dropped - Dropped connections because of a full queue. Monitor sess_conn and client_req to keep track of traffic vo...

Perhaps the most important performance metric is the hitrate. Varnish routes it's incoming requests like this: Hash, a cacheable request. This might be either hit or miss depending on the state of the cache. Hitpass, a not cacheable request. A hash with a miss and a hitpass will be fetched f...

You monitor the cached objects to see how often they expire and if they are "nuked". n_expired - Number of expired objects. n_lru_nuked - Last recently used nuked objects. Number of objects nuked (removed) from the cache because of lack of space. varnishstat -1 | grep "n_expire...

You need to keep track of some threads metrics to watch your Varnish Cache. Is it running out of OS resources or is it functioning well. threads - Number of threads in all pools. threads_created - Number of created threads. threads_failed - Number of times Varnish failed to create a thread. th...

There are a number of metrics describing the communication between Varnish and it's backends. The most important metrics here might be these: backend_busy - Number of http 5xx statuses recieved by a backend. With VCL you can configure Varnish to try another backend if this happens. backend_fail...

TypeScript catches type errors early through static analysis: function double(x: number): number { return 2 * x; } double('2'); // ~~~ Argument of type '"2"' is not assignable to parameter of type 'number'.

TypeScript enables editors to provide contextual documentation: You'll never forget whether String.prototype.slice takes (start, stop) or (start, length) again!

{-# LANGUAGE OverloadedStrings #-} module Main where import Data.Aeson main :: IO () main = do let example = Data.Aeson.object [ "key" .= (5 :: Integer), "somethingElse" .= (2 :: Integer) ] :: Value print . encode $ example

In foo.vala: void main (string[] args) { stdout.printf ("Hello world!"); } To compile the source into the foo binary: valac foo.vala To compile and run the source: vala foo.vala

project('Vala Project') glib_dep = dependency('glib-2.0') gobject_dep = dependency('gobject-2.0') executable('foo', 'foo.vala', dependencies: [glib_dep, gobject_dep]) Note: both glib-2.0 and gobject-2.0 dependencies are required unless --nostdpkg is explicitly given.

project('Posix-based Project', 'vala') add_project_arguments(['--nostdpkg'], language: 'vala') posix_dep = meson.get_compiler('vala').find_library('posix') executable('foo', 'foo.vala', dependencies: [posix_dep])

project('Mixed sources Project', 'vala') glib_dep = dependency('glib-2.0') gobject_dep = dependency('gobject-2.0') executable('foo', 'foo.vala', 'bar.c', dependencies: [glib_dep, gobject_dep]) In foo.vala: namespace Foo { public extern int bar (); public int main (string[] arg...

<?php $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, "https://api.dropboxapi.com/2/files/list_folder"); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_CAINFO, "cacert.pem"); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0); curl_setopt($ch, CURLOP...

var foo = new uint8[12]; var bar = (owned) foo; assert (foo == null); The bar variable will own the value previously owned by foo.