Class: Mustermann::AST::Pattern Abstract

Inherits:
RegexpBased show all
Extended by:
Forwardable, SingleForwardable
Defined in:
lib/mustermann/ast/pattern.rb

Overview

This class is abstract.

Superclass for pattern styles that parse an AST from the string pattern.

Direct Known Subclasses

Express, Flask, Grape, Pyramid, Rails, Sinatra, Template

Constant Summary

Constants inherited from Pattern

Pattern::PATTERN_METHODS

Constants included from Mustermann

DEFAULT_TYPE, VERSION

Instance Attribute Summary

Attributes inherited from RegexpBased

#regexp

Instance Method Summary collapse

Methods inherited from RegexpBased

#initialize, #peek_match, #peek_size

Methods inherited from Pattern

#&, #===, #=~, #^, #initialize, #match, #named_captures, #names, new, #params, #peek, #peek_match, #peek_params, #peek_size, supported?, supported_options, #to_proc, #to_s, #|

Methods included from Mustermann

[], new, register

Constructor Details

This class inherits a constructor from Mustermann::RegexpBased

Instance Method Details

#expand(behavior = nil, values = {}) ⇒ String

All AST-based pattern implementations support expanding.

Examples:

Expanding a pattern

pattern = Mustermann.new('/:name(.:ext)?')
pattern.expand(name: 'hello')             # => "/hello"
pattern.expand(name: 'hello', ext: 'png') # => "/hello.png"

Checking if a pattern supports expanding

if pattern.respond_to? :expand
  pattern.expand(name: "foo")
else
  warn "does not support expanding"
end

Parameters:

  • behavior (Symbol) (defaults to: nil) —

    What to do with additional key/value pairs not present in the values hash. Possible options: :raise, :ignore, :append.

  • values (Hash{Symbol: #to_s, Array<#to_s>}) (defaults to: {}) —

    Values to use for expansion.

Returns:

  • (String) —

    expanded string

Raises:

  • (NotImplementedError) —

    raised if expand is not supported.

  • (Mustermann::ExpandError) —

    raised if a value is missing or unknown

See Also:



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# File 'lib/mustermann/ast/pattern.rb', line 106

def expand(behavior = nil, values = {})
  @expander ||= Mustermann::Expander.new(self)
  @expander.expand(behavior, values)
end

#to_templates ⇒ Array<String>

All AST-based pattern implementations support generating templates.

Examples:

generating templates

Mustermann.new("/:name").to_templates                   # => ["/{name}"]
Mustermann.new("/:foo(@:bar)?/*baz").to_templates       # => ["/{foo}@{bar}/{+baz}", "/{foo}/{+baz}"]
Mustermann.new("/{name}", type: :template).to_templates # => ["/{name}"]

generating templates from composite patterns

pattern  = Mustermann.new('/:name')
pattern |= Mustermann.new('/{name}', type: :template)
pattern |= Mustermann.new('/example/*nested')
pattern.to_templates # => ["/{name}", "/example/{+nested}"]

Checking if a pattern supports expanding

if pattern.respond_to? :to_templates
  pattern.to_templates
else
  warn "does not support template generation"
end

Returns:

  • (Array<String>) —

    list of URI templates

See Also:



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# File 'lib/mustermann/ast/pattern.rb', line 117

def to_templates
  @to_templates ||= generate_templates(to_ast)
end