See index.js for specific line that triggered following bug:
$ ./node_modules/.bin/tsc --noEmit --watch
/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:78566
throw e;
^
TypeError: Cannot read property 'length' of undefined
at Object.find (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:207:35)
at getDeclarationWithTypeAnnotation (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:31333:31)
at isTypeRepresentableAsFunctionNamespaceMerge (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:31275:26)
at serializeMaybeAliasAssignment (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:31251:29)
at serializeVariableOrProperty (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:31059:25)
at serializeSymbolWorker (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:30927:25)
at serializeSymbol (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:30894:38)
at /tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:30875:25
at Map.forEach (<anonymous>)
at visitSymbolTable (/tmp/typescript-bug-repro/node_modules/typescript/lib/tsc.js:30874:33)