<< name1 = name1-value << name2 = << << ${name1?name 1 defined, |$name1|$name2|} stat=2 result=name 1 defined, |name1-value|| << ${name1:name 1 undefined, |$name1|$name2|} stat=0 result= << ${name2?name 2 defined, |$name1|$name2|} stat=0 result= << ${name2:name 2 undefined, |$name1|$name2|} stat=2 result=name 2 undefined, |name1-value|| << |$name1|$name2| stat=2 result=|name1-value|| << $(name1 unknown: warning: truncated macro reference: "$(name1" stat=1 result= << $(name ) unknown: warning: macro name syntax error: "name " stat=1 result= << << name2 = name2-value << << ${name1?name 1 defined, |$name1|$name2|} stat=0 result= << ${name1:name 1 undefined, |$name1|$name2|} stat=2 result=name 1 undefined, ||name2-value| << ${name2?name 2 defined, |$name1|$name2|} stat=2 result=name 2 defined, ||name2-value| << ${name2:name 2 undefined, |$name1|$name2|} stat=0 result= << |$name1|$name2| stat=2 result=||name2-value|