Crosstyan crosstyan

concept

lexical scope (static scope): dependent only on the program text.
dynamic scope: dependent on the runtime call stack.

clojure

(def x 1) default Var is static, using let for local Var, with-redefs to change the root binding var within its scope (visible in all threads).
(def ^:dynamic x 1) dynamic Var, using binding to change value (thread-local, cannot be seen by any other thread).

In example bellow:

binding only changes the value of *dynamic-var* within the scope of the binding expression

普通模式

	命令	说明 + 示例
	ds	删除括号
例	`ds` `"`	`"Hello world!"` => `Hello world!`
	cs	替换括号
例	`cs` `"(`	`"Hello world!"` => `(Hello world!)`
	cS	替换括号，括号内文本做新一行
例	`cS` `"{`	`"Hello world!"` => `{` `Hello world!` `}`

官方文档
其中PREFIX决定了所有缺省的路径

TMP_DIR      = <prefix>/tmp
STAMP_DIR    = <prefix>/src/<name>-stamp
DOWNLOAD_DIR = <prefix>/src
SOURCE_DIR   = <prefix>/src/<name>
BINARY_DIR   = <prefix>/src/<name>-build
INSTALL_DIR  = <prefix>

Kinesis Freestyle (Terrible key switches. Mushy and un-lovable)
Kinesis Freestyle Edge (Traditional layout with too many keys, mech switches, proably too big to be tented easily/properly)
Matias Ergo Pro (Looks pretty great. Have not tried.)
ErgoDox Kit (Currently, my everyday keyboard. Can buy pre-assembled on eBay.)
ErgoDox EZ (Prolly the best option for most people.)

In most programming languages, most functions are synchronous: a call to the function does all of its business in the same thread of execution. For functions meant to retrieve data, this means the data can be returned by calls to the function.

For an asynchronous function, a call to the function triggers business in some other thread, and that business (usually) does not complete until after the call returns. An asynchronous function that retrieves data via another thread cannot directly return the data to the caller because the data is not necessarily ready by the time the function returns.

In a sense, asynchronous functions are infectious: if a function foo calls an asynchronous function to conclude its business, then foo itself is asynchronous. Once you rely upon an asynchronous function to do your work, you cannot somehow remove the asynchronicity.

callbacks

When the business initiated by an asynchronous function completes, we may want to run some code in response, so the code run

Types are declared with : and not ::, and the consing operator conversely is :: instead of :
No where clauses, only let/in
The standard style is different, check http://elm-lang.org/docs/style-guide for reference
Multiline strings are a thing with """
Haskell's data corresponds to type in Elm, and also, Haskell's type corresponds to Elm's type alias
($) is (<|), but you don't use it all that much – Elm people like the flipped operator (|>) which lets you build something that reads like a pipeline
Related: Backticks will likely die soon in favour of functions that have an argument order that lends itself to pipelining with (|>)
Also, (.) is (<<), and a flipped version (>>) exists, but I don't see it used that much either
(>>=) is not an available operator and would not be polymorphic (no typeclasses, see below), and is instead commonly named SomeType.andThen – e.g. Maybe.andThen : Maybe a -> (a -> Maybe b) -> Maybe b

Most GStreamer examples found online are either for Linux or for gstreamer 0.10.

This particular release note seems to have covered important changes, such as:

ffmpegcolorspace => videoconvert
ffmpeg => libav

Applying -v will print out useful information. And most importantly the negotiation results.

	GNU ld (GNU Binutils for Ubuntu) 2.25.1
	Supported emulations:
	elf_x86_64
	elf32_x86_64
	elf_i386
	i386linux
	elf_l1om
	elf_k1om
	i386pep
	i386pe

	#please read the NSSM https://nssm.cc/usage
	Function Install-Service {
	param(
	[Parameter(Mandatory=$true)][string]$NSSMPath,
	[Parameter(Mandatory=$true)][string]$serviceName ,
	[Parameter(Mandatory=$true)][string]$serviceExecutable ,
	[Parameter(Mandatory=$false)][string]$serviceExecutableArgs ,
	[Parameter(Mandatory=$false)][string]$serviceAppDirectory ,
	[Parameter(Mandatory=$true)][string]$serviceErrorLogFile ,
	[Parameter(Mandatory=$true)][string]$serviceOutputLogFile ,

	@echo off
	FOR /f "tokens=*" %%i IN ('docker ps -aq') DO docker rm %%i
	FOR /f "tokens=*" %%i IN ('docker images --format "{{.ID}}"') DO docker rmi %%i