Class: TemplatePage::Context

Inherits:
Object
  • Object
show all
Defined in:
lib/rdoc/template.rb

Overview

######## A context holds a stack of key/value pairs (like a symbol table). When asked to resolve a key, it first searches the top of the stack, then the next level, and so on until it finds a match (or runs out of entries)

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Context

Returns a new instance of Context.



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# File 'lib/rdoc/template.rb', line 47

def initialize
  @stack = []
end

Instance Method Details

#find_scalar(key) ⇒ Object

Find a scalar value, throwing an exception if not found. This method is used when substituting the %xxx% constructs



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# File 'lib/rdoc/template.rb', line 62

def find_scalar(key)
  @stack.reverse_each do |level|
    if val = level[key]
      return val unless val.kind_of? Array
    end
  end
  raise "Template error: can't find variable '#{key}'"
end

#lookup(key) ⇒ Object

Lookup any key in the stack of hashes



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# File 'lib/rdoc/template.rb', line 73

def lookup(key)
  @stack.reverse_each do |level|
    val = level[key]
    return val if val
  end
  nil
end

#pop ⇒ Object 



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# File 'lib/rdoc/template.rb', line 55

def pop
  @stack.pop
end

#push(hash) ⇒ Object 



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# File 'lib/rdoc/template.rb', line 51

def push(hash)
  @stack.push(hash)
end