class Toys::DSL::Flag
DSL
for a flag definition block. Lets you set flag attributes in a block instead of a long series of keyword arguments.
These directives are available inside a block passed to {Toys::DSL::Tool#flag}.
### Example
tool "mytool" do flag :value do # The directives in here are defined by this class flags "--value=VAL" accept Integer desc "An integer value" end # ... end
Public Class Methods
@private
# File lib/toys/dsl/flag.rb, line 26 def initialize(flags, acceptor, default, handler, flag_completion, value_completion, report_collisions, group, desc, long_desc, display_name) @flags = flags @default = default @handler = handler @report_collisions = report_collisions @group = group @desc = desc @long_desc = long_desc || [] @display_name = display_name accept(acceptor) complete_flags(flag_completion, **{}) complete_values(value_completion, **{}) end
Public Instance Methods
@private
# File lib/toys/dsl/flag.rb, line 288 def _add_to(tool, key) tool.add_flag(key, @flags, accept: @acceptor, default: @default, handler: @handler, complete_flags: @flag_completion, complete_values: @value_completion, report_collisions: @report_collisions, group: @group, desc: @desc, long_desc: @long_desc, display_name: @display_name) end
Set the acceptor for this flag's values. You can pass either the string name of an acceptor defined in this tool or any of its ancestors, or any other specification recognized by {Toys::Acceptor.create}.
@param spec [Object] @param options [Hash] @param block [Proc] @return [self]
# File lib/toys/dsl/flag.rb, line 116 def accept(spec = nil, **options, &block) @acceptor = Acceptor.scalarize_spec(spec, options, block) self end
Set the shell completion strategy for flag names. You can pass one of the following:
* The string name of a completion defined in this tool or any of its ancestors. * A hash of options to pass to the constructor of {Toys::Flag::DefaultCompletion}. * `nil` or `:default` to select the standard completion strategy (which is {Toys::Flag::DefaultCompletion} with no extra options). * Any other specification recognized by {Toys::Completion.create}.
@param spec [Object] @param options [Hash] @param block [Proc] @return [self]
# File lib/toys/dsl/flag.rb, line 165 def complete_flags(spec = nil, **options, &block) @flag_completion = Completion.scalarize_spec(spec, options, block) self end
Set the shell completion strategy for flag values. You can pass either the string name of a completion defined in this tool or any of its ancestors, or any other specification recognized by {Toys::Completion.create}.
@param spec [Object] @param options [Hash] @param block [Proc] @return [self]
# File lib/toys/dsl/flag.rb, line 181 def complete_values(spec = nil, **options, &block) @value_completion = Completion.scalarize_spec(spec, options, block) self end
Set the default value.
@param default [Object] @return [self]
# File lib/toys/dsl/flag.rb, line 127 def default(default) @default = default self end
Set the short description for the current flag. The short description is displayed with the flag in online help.
The description is a {Toys::WrappableString}, which may be word-wrapped when displayed in a help screen. You may pass a {Toys::WrappableString} directly to this method, or you may pass any input that can be used to construct a wrappable string:
* If you pass a String, its whitespace will be compacted (i.e. tabs, newlines, and multiple consecutive whitespace will be turned into a single space), and it will be word-wrapped on whitespace. * If you pass an Array of Strings, each string will be considered a literal word that cannot be broken, and wrapping will be done across the strings in the array. In this case, whitespace is not compacted.
### Examples
If you pass in a sentence as a simple string, it may be word wrapped when displayed:
desc "This sentence may be wrapped."
To specify a sentence that should never be word-wrapped, pass it as the sole element of a string array:
desc ["This sentence will not be wrapped."]
@param desc [String,Array<String>,Toys::WrappableString] @return [self]
# File lib/toys/dsl/flag.rb, line 230 def desc(desc) @desc = desc self end
Set the display name for this flag. This may be used in help text and error messages.
@param display_name
[String] @return [self]
# File lib/toys/dsl/flag.rb, line 282 def display_name(display_name) @display_name = display_name self end
Add flags in OptionParser format. This may be called multiple times, and the results are cumulative.
Following are examples of valid syntax.
* `-a` : A short boolean switch. When this appears as an argument, the value is set to `true`. * `--abc` : A long boolean switch. When this appears as an argument, the value is set to `true`. * `-aVAL` or `-a VAL` : A short flag that takes a required value. These two forms are treated identically. If this argument appears with a value attached (e.g. `-afoo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, the following argument is taken as the value (e.g. for `-a foo`, the value is set to `"foo"`.) The following argument is treated as the value even if it looks like a flag (e.g. `-a -a` causes the string `"-a"` to be taken as the value.) * `-a[VAL]` : A short flag that takes an optional value. If this argument appears with a value attached (e.g. `-afoo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, the value is set to `true`. The following argument is never interpreted as the value. (Compare with `-a [VAL]`.) * `-a [VAL]` : A short flag that takes an optional value. If this argument appears with a value attached (e.g. `-afoo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, if the following argument does not look like a flag (i.e. it does not begin with a hyphen), it is taken as the value. (e.g. `-a foo` causes the string `"foo"` to be taken as the value.). If there is no following argument, or the following argument looks like a flag, the value is set to `true`. (Compare with `-a[VAL]`.) * `--abc=VAL` or `--abc VAL` : A long flag that takes a required value. These two forms are treated identically. If this argument appears with a value attached (e.g. `--abc=foo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, the following argument is taken as the value (e.g. for `--abc foo`, the value is set to `"foo"`.) The following argument is treated as the value even if it looks like a flag (e.g. `--abc --def` causes the string `"--def"` to be taken as the value.) * `--abc[=VAL]` : A long flag that takes an optional value. If this argument appears with a value attached (e.g. `--abc=foo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, the value is set to `true`. The following argument is never interpreted as the value. (Compare with `--abc [VAL]`.) * `--abc [VAL]` : A long flag that takes an optional value. If this argument appears with a value attached (e.g. `--abc=foo`), the attached string (e.g. `"foo"`) is taken as the value. Otherwise, if the following argument does not look like a flag (i.e. it does not begin with a hyphen), it is taken as the value. (e.g. `--abc foo` causes the string `"foo"` to be taken as the value.). If there is no following argument, or the following argument looks like a flag, the value is set to `true`. (Compare with `--abc=[VAL]`.) * `--[no-]abc` : A long boolean switch that can be turned either on or off. This effectively creates two flags, `--abc` which sets the value to `true`, and `--no-abc` which sets the falue to `false`.
@param flags [String…] @return [self]
# File lib/toys/dsl/flag.rb, line 100 def flags(*flags) @flags += flags.flatten self end
Set the group. A group may be set by name or group object. Setting `nil` selects the default group.
@param group [String,Symbol,Toys::FlagGroup,nil] @return [self]
# File lib/toys/dsl/flag.rb, line 270 def group(group) @group = group self end
Set the optional handler for setting/updating the value when a flag is parsed. A handler should be a Proc taking two arguments, the new given value and the previous value, and it should return the new value that should be set. You may pass the handler as a Proc (or an object responding to the `call` method) or you may pass a block.
@param handler [Proc] @param block [Proc] @return [self]
# File lib/toys/dsl/flag.rb, line 143 def handler(handler = nil, &block) @handler = handler || block self end
Add to the long description for the current flag. The long description is displayed with the flag in online help. This directive may be given multiple times, and the results are cumulative.
A long description is a series of descriptions, which are generally displayed in a series of lines/paragraphs. Each individual description uses the form described in the {#desc} documentation, and may be word-wrapped when displayed. To insert a blank line, include an empty string as one of the descriptions.
### Example
long_desc "This initial paragraph might get word wrapped.", "This next paragraph is followed by a blank line.", "", ["This line will not be wrapped."], [" This indent is preserved."] long_desc "This line is appended to the description."
@param long_desc
[String,Array<String>,Toys::WrappableString…] @return [self]
# File lib/toys/dsl/flag.rb, line 258 def long_desc(*long_desc) @long_desc += long_desc self end
Set whether to raise an exception if a flag is requested that is already in use or marked as disabled.
@param setting [Boolean] @return [self]
# File lib/toys/dsl/flag.rb, line 193 def report_collisions(setting) @report_collisions = setting self end