Parsing quotation is slow

[neverRare]

While translating quotations isn't prioritized for now. A bug where parsing quotation mark causes infinite loop should be fixed. It may not actually be an infinite loop but a very slow computation, parsing " parses within several seconds.

[neverRare]

After introduction of lexer, it is a little better but still slow. This is odd!

[neverRare]

after a refactor, parsing quotation mark were removed

[neverRare]

may be reopened after reimplementing quotation