YAML sucks.

YAML specification is so ambigous, that you can't be sure if tomorrow you will parse the same data from YAML file as you have yesterday.

Let's see how different implementations parse YAML code. Settings are default or near to default or typical for that language. We use JSON to represent data the uniform way.

YAML source	yaml2json.hs	yaml2json.pl	yaml2json.py	yaml2json.rb
- false - n - off	[false,false,false]	["","n","off"]	[false, "n", false]	[false,"n",false]
	❌ yaml2json.hs: Unexpected event: expected Nothing but received Just EventStreamStart	null	null	false
- 1.23015e+3 - 12.3015e+02 - 1230.15 - -.inf - .NaN	[1230.15,1230.15,1230.15,"-.inf",".NaN"]	["1.23015e+3","12.3015e+02","1230.15","-.inf",".NaN"]	[1230.15, 1230.15, 1230.15, -Infinity, NaN]	[1230.15,1230.15,1230.15,-Infinity,NaN]
0xC	"0xC"	"0xC"	12	12
<<	"<<"	"<<"	❌ ConstructorError: could not determine a constructor for the tag 'tag:yaml.org,2002:merge' in "", line 1, column 1	"<<"
<<: {}	{}	{"<<":{}}	{}	{}
"<<": {}	{}	{"<<":{}}	{"<<": {}}	{}
<<: a	{"<<":"a"}	{"<<":"a"}	❌ ConstructorError: while constructing a mapping in "", line 1, column 1 expected a mapping or list of mappings for merging, but found scalar in "", line 1, column 5	{"<<":"a"}
- 1000 - +1000 - 1_000	[1000,1000,"1_000"]	["1000","+1000","1_000"]	[1000, 1000, 1000]	[1000,1000,1000]
[8, 08, 0o10]	[8,8,"0o10"]	["8","08","0o10"]	[8, "08", "0o10"]	[8,"08","0o10"]
"Sosa did fine.\u263A"	"Sosa did fine.☺"	❌ Wide character in say at ./yaml2json.pl line 10, <> line 1.	"Sosa did fine.\u263a"	"Sosa did fine.☺"