gistfile1.txt

      ladders = @strategies.map { |strategy| strategy.crank(bar) }.compact
      if verbose && ladders.any? { |ladder| ladder.changed? }
        ladder = Ladder.consolidate ladders
        write ladder
      end

PRODUCES:

RubyArray.java:2031:in `compact_bang': java.lang.NullPointerException
	from RubyArray.java:2052:in `compact'
	from org/jruby/RubyArray$i_method_0_0$RUBYINVOKER$compact.gen:-1:in `call'
	from CachingCallSite.java:106:in `call'
	from CallNoArgNode.java:61:in `interpret'
	from LocalAsgnNode.java:123:in `interpret'
	from NewlineNode.java:104:in `interpret'
	from BlockNode.java:71:in `interpret'
	from WhileNode.java:131:in `interpret'
	from NewlineNode.java:104:in `interpret'
	from BlockNode.java:71:in `interpret'
	from InterpretedMethod.java:180:in `call'
	from DefaultMethod.java:172:in `call'
	from CachingCallSite.java:309:in `cacheAndCall'
	from CachingCallSite.java:148:in `call'
	from gf_enq.rb:101:in `block_11$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyNumeric.java:807:in `fixnumStep'
	from RubyNumeric.java:791:in `stepCommon19'
	from RubyNumeric.java:785:in `step19'
	from org/jruby/RubyNumeric$i_method_multi$RUBYFRAMEDINVOKER$step19.gen:-1:in `call'
	from CachingCallSite.java:339:in `cacheAndCall'
	from CachingCallSite.java:197:in `callBlock'
	from CachingCallSite.java:212:in `callIter'
	from gf_enq.rb:91:in `block_10$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:89:in `block_9$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:88:in `block_8$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:87:in `block_7$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:85:in `block_6$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:82:in `block_5$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:64:in `block_4$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:62:in `block_3$RUBY$__block__'
	from null:-1:in `call'
	from CompiledBlock.java:115:in `yield'
	from CompiledBlock.java:98:in `yield'
	from Block.java:194:in `yield'
	from RubyArray.java:1644:in `eachCommon'
	from RubyArray.java:1651:in `each'
	from org/jruby/RubyArray$i_method_0_0$RUBYFRAMEDINVOKER$each.gen:-1:in `call'
	from CachingCallSite.java:299:in `cacheAndCall'
	from CachingCallSite.java:117:in `callBlock'
	from CachingCallSite.java:132:in `callIter'
	from gf_enq.rb:61:in `ensure_1$RUBY$__ensure___2'
	from gf_enq.rb:42:in `__file__'
	from gf_enq.rb:-1:in `load'
	from Ruby.java:647:in `runScript'
	from Ruby.java:565:in `runNormally'
	from Ruby.java:411:in `runFromMain'
	from Main.java:272:in `run'
	from Main.java:117:in `run'
	from Main.java:97:in `main'