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Avoid recalculating reduce_rules - #28

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Josh Holtrop 2024-07-26 21:36:41 -04:00
parent 95b3dc6550
commit 61339aeae9
1 changed files with 4 additions and 4 deletions
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8
lib/propane/parser.rb
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@ -140,20 +140,20 @@ class Propane
if reduce_rules.size == 0 if reduce_rules.size == 0
nil nil
else else
build_lookahead_reduce_actions_for_item_set(item_set) build_lookahead_reduce_actions_for_item_set(reduce_rules, item_set)
end end
end end
# Build the reduce actions for a single item set (parser state). # Build the reduce actions for a single item set (parser state).
# #
# @param reduce_rules [Set<Rule>]
# Rules to look for lookahead tokens after.
# @param item_set [ItemSet] # @param item_set [ItemSet]
# ItemSet (parser state) # ItemSet (parser state)
# #
# @return [Hash] # @return [Hash]
# Mapping of lookahead Tokens to the Rules to reduce. # Mapping of lookahead Tokens to the Rules to reduce.
def build_lookahead_reduce_actions_for_item_set(item_set) def build_lookahead_reduce_actions_for_item_set(reduce_rules, item_set)
reduce_rules = Set.new(item_set.items.select(&:complete?).map(&:rule))
# We will be looking for all possible tokens that can follow instances of # We will be looking for all possible tokens that can follow instances of
# these rules. Rather than looking through the entire grammar for the # these rules. Rather than looking through the entire grammar for the
# possible following tokens, we will only look in the item sets leading # possible following tokens, we will only look in the item sets leading