74 lines
1.5 KiB
Ruby
74 lines
1.5 KiB
Ruby
# frozen_string_literal: true
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module Rpl
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module Lang
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class Dictionary
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attr_reader :vars,
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:local_vars_layers
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def initialize
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@words = {}
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@vars = {}
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@local_vars_layers = []
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end
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def add( name, implementation )
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@words[ name ] = implementation
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end
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def add_var( name, implementation )
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@vars[ name ] = implementation
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end
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def remove_vars( names )
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names.each do |name|
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@vars.delete( name )
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end
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end
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def remove_var( name )
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remove_vars( [name] )
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end
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def remove_all_vars
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@vars = {}
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end
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def add_local_vars_layer
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@local_vars_layers << {}
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end
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def add_local_var( name, implementation )
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@local_vars_layers.last[ name ] = implementation
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end
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def remove_local_vars( names )
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names.each do |name|
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@local_vars_layers.last.delete( name )
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end
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end
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def remove_local_var( name )
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remove_local_vars( [name] )
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end
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def remove_local_vars_layer
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@local_vars_layers.pop
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end
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def lookup( name )
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# look in local variables from the deepest layer up
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local_vars_layer = @local_vars_layers.reverse.find { |layer| layer[ name ] }
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word = local_vars_layer.nil? ? nil : local_vars_layer[ name ]
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# otherwise look in (global) variables
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word ||= @vars[ name ]
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# or is it a core word
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word ||= @words[ name ]
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word
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end
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end
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end
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end
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