Vergleich von Optionstypen

Beste Broker fur Binare Optionen 2020:
  • Binarium

    Der beste Broker fur binare Optionen fur 2020!
    Ideal fur Anfanger!
    Kostenloser Unterricht!

  • FinMax

    2 Platz in der Rangliste! Zuverlassiger Broker.

Functional Options in Go

Functional options are an idiomatic way of creating APIs with options on types. The initial idea for this design pattern can be found in an article published by Rob Pike called Self-referential functions and the design of options.

The following code snippet provides a brief example of the use of functional options:


Adding options to commands can be accomplished by the option() decorator. Since options can come in various different versions, there are a ton of parameters to configure their behavior. Options in click are distinct from positional arguments .

Name Your Options¶

Options have a name that will be used as the Python argument name when calling the decorated function. This can be inferred from the option names or given explicitly. Names are given as position arguments to the decorator.

A name is chosen in the following order

If a name is not prefixed, it is used as the Python argument name and not treated as an option name on the command line.

If there is at least one name prefixed with two dashes, the first one given is used as the name.

The first name prefixed with one dash is used otherwise.

To get the Python argument name, the chosen name is converted to lower case, up to two dashes are removed as the prefix, and other dashes are converted to underscores.

„-f“, „–foo-bar“ , the name is foo_bar

„-x“ , the name is x

„-f“, „–filename“, „dest“ , the name is dest

Beste Broker fur Binare Optionen 2020:
  • Binarium

    Der beste Broker fur binare Optionen fur 2020!
    Ideal fur Anfanger!
    Kostenloser Unterricht!

  • FinMax

    2 Platz in der Rangliste! Zuverlassiger Broker.

„–CamelCase“ , the name is camelcase

„-f“, „-fb“ , the name is f

„–f“, „–foo-bar“ , the name is f

„—f“ , the name is _f

Basic Value Options¶

The most basic option is a value option. These options accept one argument which is a value. If no type is provided, the type of the default value is used. If no default value is provided, the type is assumed to be STRING . Unless a name is explicitly specified, the name of the parameter is the first long option defined; otherwise the first short one is used. By default, options are not required, however to make an option required, simply pass in required=True as an argument to the decorator.

And on the command line:

In this case the option is of type INT because the default value is an integer.

To show the default values when showing command help, use show_default=True

Multi Value Options¶

Sometimes, you have options that take more than one argument. For options, only a fixed number of arguments is supported. This can be configured by the nargs parameter. The values are then stored as a tuple.

And on the command line:

Tuples as Multi Value Options¶

New in version 4.0.

As you can see that by using nargs set to a specific number each item in the resulting tuple is of the same type. This might not be what you want. Commonly you might want to use different types for different indexes in the tuple. For this you can directly specify a tuple as type:

And on the command line:

By using a tuple literal as type, nargs gets automatically set to the length of the tuple and the click.Tuple type is automatically used. The above example is thus equivalent to this:

Multiple Options¶

Similarly to nargs , there is also the case of wanting to support a parameter being provided multiple times and have all the values recorded – not just the last one. For instance, git commit -m foo -m bar would record two lines for the commit message: foo and bar . This can be accomplished with the multiple flag:

And on the command line:

When passing a default with multiple=True , the default value must be a list or tuple, otherwise it will be interpreted as a list of single characters.


In some very rare circumstances, it is interesting to use the repetition of options to count an integer up. This can be used for verbosity flags, for instance:

And on the command line:

Boolean Flags¶

Boolean flags are options that can be enabled or disabled. This can be accomplished by defining two flags in one go separated by a slash ( / ) for enabling or disabling the option. (If a slash is in an option string, Click automatically knows that it’s a boolean flag and will pass is_flag=True implicitly.) Click always wants you to provide an enable and disable flag so that you can change the default later.

And on the command line:

If you really don’t want an off-switch, you can just define one and manually inform Click that something is a flag:

And on the command line:

Note that if a slash is contained in your option already (for instance, if you use Windows-style parameters where / is the prefix character), you can alternatively split the parameters through ; instead:

Changed in version 6.0.

If you want to define an alias for the second option only, then you will need to use leading whitespace to disambiguate the format string:

Feature Switches¶

In addition to boolean flags, there are also feature switches. These are implemented by setting multiple options to the same parameter name and defining a flag value. Note that by providing the flag_value parameter, Click will implicitly set is_flag=True .

To set a default flag, assign a value of True to the flag that should be the default.

And on the command line:

Choice Options¶

Sometimes, you want to have a parameter be a choice of a list of values. In that case you can use Choice type. It can be instantiated with a list of valid values. The originally passed choice will be returned, not the str passed on the command line. Token normalization functions and case_sensitive=False can cause the two to be different but still match.

What it looks like:

Only pass the choices as list or tuple. Other iterables (like generators) may lead to unexpected results.

Choices work with options that have multiple=True . If a default value is given with multiple=True , it should be a list or tuple of valid choices.

Choices should be unique after considering the effects of case_sensitive and any specified token normalization function.

Changed in version 7.1: The resulting value from an option will always be on the of the originally passed choices regardless of case_sensitive .


In some cases, you want parameters that can be provided from the command line, but if not provided, ask for user input instead. This can be implemented with Click by defining a prompt string.

And what it looks like:

If you are not happy with the default prompt string, you can ask for a different one:

What it looks like:

It is advised that prompt not be used in conjunction with the multiple flag set to True. Instead, prompt in the function interactively.

Password Prompts¶

Click also supports hidden prompts and asking for confirmation. This is useful for password input:

What it looks like:

Because this combination of parameters is quite common, this can also be replaced with the password_option() decorator:

Dynamic Defaults for Prompts¶

The auto_envvar_prefix and default_map options for the context allow the program to read option values from the environment or a configuration file. However, this overrides the prompting mechanism, so that the user does not get the option to change the value interactively.

If you want to let the user configure the default value, but still be prompted if the option isn’t specified on the command line, you can do so by supplying a callable as the default value. For example, to get a default from the environment:

To describe what the default value will be, set it in show_default .

Callbacks and Eager Options¶

Sometimes, you want a parameter to completely change the execution flow. For instance, this is the case when you want to have a –version parameter that prints out the version and then exits the application.

Note: an actual implementation of a –version parameter that is reusable is available in Click as click.version_option() . The code here is merely an example of how to implement such a flag.

In such cases, you need two concepts: eager parameters and a callback. An eager parameter is a parameter that is handled before others, and a callback is what executes after the parameter is handled. The eagerness is necessary so that an earlier required parameter does not produce an error message. For instance, if –version was not eager and a parameter –foo was required and defined before, you would need to specify it for –version to work. For more information, see Callback Evaluation Order .

A callback is a function that is invoked with two parameters: the current Context and the value. The context provides some useful features such as quitting the application and gives access to other already processed parameters.

Here an example for a –version flag:

The expose_value parameter prevents the pretty pointless version parameter from being passed to the callback. If that was not specified, a boolean would be passed to the hello script. The resilient_parsing flag is applied to the context if Click wants to parse the command line without any destructive behavior that would change the execution flow. In this case, because we would exit the program, we instead do nothing.

What it looks like:

Callback Signature Changes

In Click 2.0 the signature for callbacks changed. For more information about these changes see Upgrading to 2.0 .

Yes Parameters¶

For dangerous operations, it’s very useful to be able to ask a user for confirmation. This can be done by adding a boolean –yes flag and asking for confirmation if the user did not provide it and to fail in a callback:

And what it looks like on the command line:

Because this combination of parameters is quite common, this can also be replaced with the confirmation_option() decorator:

Callback Signature Changes

In Click 2.0 the signature for callbacks changed. For more information about these changes see Upgrading to 2.0 .

Values from Environment Variables¶

A very useful feature of Click is the ability to accept parameters from environment variables in addition to regular parameters. This allows tools to be automated much easier. For instance, you might want to pass a configuration file with a –config parameter but also support exporting a TOOL_CONFIG=hello.cfg key-value pair for a nicer development experience.

This is supported by Click in two ways. One is to automatically build environment variables which is supported for options only. To enable this feature, the auto_envvar_prefix parameter needs to be passed to the script that is invoked. Each command and parameter is then added as an uppercase underscore-separated variable. If you have a subcommand called run taking an option called reload and the prefix is WEB , then the variable is WEB_RUN_RELOAD .

And from the command line:

When using auto_envvar_prefix with command groups, the command name needs to be included in the environment variable, between the prefix and the parameter name, i.e. PREFIX_COMMAND_VARIABLE . If you have a subcommand called run-server taking an option called host and the prefix is WEB , then the variable is WEB_RUN_SERVER_HOST .

The second option is to manually pull values in from specific environment variables by defining the name of the environment variable on the option.

And from the command line:

In that case it can also be a list of different environment variables where the first one is picked.

Multiple Values from Environment Values¶

As options can accept multiple values, pulling in such values from environment variables (which are strings) is a bit more complex. The way Click solves this is by leaving it up to the type to customize this behavior. For both multiple and nargs with values other than 1 , Click will invoke the ParamType.split_envvar_value() method to perform the splitting.

The default implementation for all types is to split on whitespace. The exceptions to this rule are the File and Path types which both split according to the operating system’s path splitting rules. On Unix systems like Linux and OS X, the splitting happens for those on every colon ( : ), and for Windows, on every semicolon ( ; ).

And from the command line:

Other Prefix Characters¶

Click can deal with alternative prefix characters other than – for options. This is for instance useful if you want to handle slashes as parameters / or something similar. Note that this is strongly discouraged in general because Click wants developers to stay close to POSIX semantics. However in certain situations this can be useful:

And from the command line:

Note that if you are using / as prefix character and you want to use a boolean flag you need to separate it with ; instead of / :

Range Options¶

A special mention should go to the IntRange type, which works very similarly to the INT type, but restricts the value to fall into a specific range (inclusive on both edges). It has two modes:

the default mode (non-clamping mode) where a value that falls outside of the range will cause an error.

an optional clamping mode where a value that falls outside of the range will be clamped. This means that a range of 0-5 would return 5 for the value 10 or 0 for the value -1 (for example).

And from the command line:

If you pass None for any of the edges, it means that the range is open at that side.

Callbacks for Validation¶

Changed in version 2.0.

If you want to apply custom validation logic, you can do this in the parameter callbacks. These callbacks can both modify values as well as raise errors if the validation does not work.

In Click 1.0, you can only raise the UsageError but starting with Click 2.0, you can also raise the BadParameter error, which has the added advantage that it will automatically format the error message to also contain the parameter name.

Vergleich von Optionstypen

GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together.

VON / options / /

from . base_options import BaseOptions
class TestOptions ( BaseOptions ):
def initialize ( self , parser ):
BaseOptions . initialize ( self , parser )
parser . add_argument ( ‚–results_dir‘ , type = str , default = ‚../results/‘ , help = ’saves results here.‘ )
parser . add_argument ( ‚–n_shapes‘ , type = int , default = 10 , help = ‚the number of sampled shapes‘ )
parser . add_argument ( ‚–n_views‘ , type = int , default = 10 , help = ‚the number of sampled views‘ )
parser . add_argument ( ‚–reset_shape‘ , action = ’store_true‘ , help = ’sample a different shape‘ )
parser . add_argument ( ‚–reset_texture‘ , action = ’store_true‘ , help = ’sample a different texture‘ )
parser . add_argument ( ‚–real_shape‘ , action = ’store_true‘ , help = ‚use real voxels‘ )
parser . add_argument ( ‚–real_texture‘ , action = ’store_true‘ , help = ‚use real textures‘ )
parser . add_argument ( ‚–render_3d‘ , action = ’store_true‘ , help = ‚use blender to render 3d‘ )
parser . add_argument ( ‚–render_25d‘ , action = ’store_true‘ , help = ‚use blender to render 2.5d‘ )
parser . add_argument ( ‚–random_view‘ , action = ’store_true‘ , help = ’show random views‘ )
parser . add_argument ( ‚–show_input‘ , action = ’store_true‘ , help = ’show input image‘ )
parser . add_argument ( ‚–interp_shape‘ , action = ’store_true‘ , help = ‚interpolate in shape space‘ )
parser . add_argument ( ‚–interp_texture‘ , action = ’store_true‘ , help = ‚interpolate in texture space‘ )
parser . add_argument ( ‚–aspect_ratio‘ , type = float , default = 1.0 , help = ‚aspect ratio for the results‘ )
parser . add_argument ( ‚–ios_th‘ , default = 0.01 , type = float , help = ‚thresholding for isosurface‘ )
self . isTrain = False
return parser
  • © 2020 GitHub, Inc.
  • Terms
  • Privacy
  • Security
  • Status
  • Help

You can’t perform that action at this time.

You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session.


API Reference


UI-related richselect is a non-editable combo-box.

Visually, the richselect control consists of a text input and popup window that contains a standard list of options in its body.

Another possibility to create a component with a similar functionality is attaching a suggest list to a text field, but in this case, text field will be editable.


Main Properties

  • value (string, number)
    • within options array it sets text value for selectable items;
    • within richselect constructor it defines the initially selected item of the control (ID in case of a long form, text value in case of a short form of initialization);
  • placeholder (string) – defines placeholder for richselect input. The control should be initialized without an initial value;
  • label (string) – text label of a control. It can be customized by:
    • labelAlign (string) – label alignment towards its container. Possible values are „left“ and „right“. In any way, it’s placed left to the control;
    • labelWidth (number) – width of the label container;
  • options (array, object, string) – sets the options to choose from in a long or short form. Details.

Configuring Suggest List

Richselect control can be customized in a number of ways, e.g.:

  • options can be defined dynamically;
  • options can be loaded from server side;
  • template can be changed.

You can customize the default suggest list configuration, learn more in the Advanced Settings of Popup Selectors article.

Accessing Suggest List

Richselect API provides a set of techniques for getting popup and list objects for further usage. The examples below illustrate available options:

Pro Extensions for Richselect

In the Webix Pro edition the control can be extended to show either a DataView or DataTable in the popup:

Getting Current Value

In case of a full initialization form, the getValue() method for richselect will return ID of selected option rather than text. Use getText() method to get text value.

Beste Broker fur Binare Optionen 2020:
  • Binarium

    Der beste Broker fur binare Optionen fur 2020!
    Ideal fur Anfanger!
    Kostenloser Unterricht!

  • FinMax

    2 Platz in der Rangliste! Zuverlassiger Broker.

Like this post? Please share to your friends:
Alles über Binäre Optionen
Schreibe einen Kommentar

;-) :| :x :twisted: :smile: :shock: :sad: :roll: :razz: :oops: :o :mrgreen: :lol: :idea: :grin: :evil: :cry: :cool: :arrow: :???: :?: :!: