Error in parse_amr_single.sh - stringx.lua:27: argument 1 expected a 'string', got a 'nil'

[around1991]

Many thanks for releasing the parser!

I'm trying to run the parser on some sample sentences, and it all works until it produces the following stack trace:

stack traceback:
	[C]: in function 'error'
	...lespace-2/kc391/torch/install/share/lua/5.1/pl/utils.lua:429: in function 'assert_arg'
	...space-2/kc391/torch/install/share/lua/5.1/pl/stringx.lua:27: in function 'assert_string'
	...space-2/kc391/torch/install/share/lua/5.1/pl/stringx.lua:266: in function 'replace'
	evaluate.lua:107: in function 'clean'
	evaluate.lua:91: in function 'parse'
	evaluate.lua:53: in function 'main'
	evaluate.lua:206: in main chunk
	[C]: in function 'dofile'
	...c391/torch/install/lib/luarocks/rocks/trepl/scm-1/bin/th:150: in main chunk
	[C]: at 0x00405d50

Do you know what could be going wrong?

Kris