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proc myproc args { ... } proc myproc {args} { ... } ;# equivalent If the special parameter name args is the last item in the argument list, it receives a list of all arguments at that point in the command line. If there are none, the list is empty. There can be arguments, including optional one...

proc myproc {varName alpha beta} { upvar 1 $varName var set var [expr {$var * $alpha + $beta}] } set foo 1 myproc foo 10 5 puts $foo # => 15 In this particular case, the procedure is given the name of a variable in the current scope. Inside a Tcl procedure, such variables aren't...

# application.rb config.time_zone = 'Eastern Time (US & Canada)'

Creating a namedtuple with type hints is done using the function NamedTuple from the typing module: import typing Point = typing.NamedTuple('Point', [('x', int), ('y', int)]) Note that the name of the resulting type is the first argument to the function, but it should be assigned to a variable ...

PostgreSQL is an actively developed and mature open source database. Using the psycopg2 module, we can execute queries on the database. Installation using pip pip install psycopg2 Basic usage Lets assume we have a table my_table in the database my_database defined as follows. idfirst_namelast_n...

Loops can be nested, to preform iterated task within another iterated task. Consider the following loops: ch = 'abc'; m = 3; for c = ch for k = 1:m disp([c num2str(k)]) % NUM2STR converts the number stored in k to a charachter, % so it can be concatanet...

Once you have both your server-side logging running, and your client side development tools, you can start looking at Meteor specific extensions like the Meteor Chrome DevTools Extension. This lets you actually observe server logging in the client! Because the database is everywhere. As is logging. ...

The following uses the Chrome Logging API. If the .group() syntax is used in multiple templates, it will graphically organize the console logs from different templates into a hierarchical tree. You can also see how to inspect the current data context, and how to stringify data. Template.landingPa...

For server side debugging, you'll need to use a tool like Node Inspector. Before you get started, check out some of these useful tutorials. HowToNode - Debugging with Node Inspector Strongloop - Debugging Applications Easily Debugging Meteor.js Walkthrough with Screenshots of Using Node Inspecto...

Besides Node Inspector, some people have reported success with a npm utility called debug. MeteorHacks - Debugging Meteor with npm debug

It's possible to combine all of the above into expressive ranges: :1267,/foo/-2command :'{,command :'f,$command Be creative and don't forget to read :help cmdline-ranges.

In elm, a function's value is computed when the last argument is applied. In the example below, the diagnostic from log will be printed when f is invoked with 3 arguments or a curried form of f is applied with the last argument. import String import Debug exposing (log) f a b c = String.join &...

There are currently three YouTube APIs available to the public: YouTube Data API YouTube Analytics API YouTube Reporting API Each of these offer different functionality and are treated as separate, individual APIs. Since YouTube is a subsidiary of Google, the various YouTube APIs are provid...

POST /token HTTP/1.1 Host: server.example.com Content-Type: application/x-www-form-urlencoded grant_type=client_credentials&client_id=[APP_KEY]&client_secret=[APP_SECRET] Source

POST /token HTTP/1.1 Host: server.example.com Content-Type: application/x-www-form-urlencoded grant_type=password&username=[USERNAME]&password=[PASSWORD] &client_id=[APP_KEY]&client_secret=[APP_SECRET] Source

Roles also enable you to define other roles as a dependency by creating a meta/main.yml file with a dependencies block: dependencies: - role: common It's also possible to pass a value to a parameter/variable in the dependent role: dependencies: - { role: common, some_parameter: 3 } Or ...

The special LOOP NAMED foo syntax allows you to create a loop that you can exit early from. The exit is performed using return-from, and can be used from within nested loops. The following uses a nested loop to look for a complex number in a 2D array: (loop named top for x from 0 below (arr...

With the Class Based generic Views, it is very simple and easy to create the CRUD views from our models. Often, the built in Django admin is not enough or not preferred and we need to roll our own CRUD views. The CBVs can be very handy in such cases. The CreateView class needs 3 things - a model, t...

Starting with a three-dimensional list: alist = [[[1,2],[3,4]], [[5,6,7],[8,9,10], [12, 13, 14]]] Accessing items in the list: print(alist[0][0][1]) #2 #Accesses second element in the first list in the first list print(alist[1][1][2]) #10 #Accesses the third element in the second list in...

There are two different types of descriptors. Data descriptors are defined as objects that define both a __get__() and a __set__() method, whereas non-data descriptors only define a __get__() method. This distinction is important when considering overrides and the namespace of an instance's dictiona...