🚧 Under development, not stable yet 🚧
It does not use exceptions and instead returns a result object. Library is composable and concise.
- Update Gemfile with
gem 'dolos'
- Run bundle install
require 'dolos'
include Dolos
ws = c(" ")
parser = c("Parsers") & ws & c("are") & ws & c("great!")
parser.run("Parsers are great!") # <Result::Success>
greeter = c("Hello")
greet_and_speak = greeter & c(", ") & parser
greet_and_speak.run("Hello, Parsers are great!") # <Result::Success>
require 'dolos'
include Dolos
# Include common parsers
# In future this can be more structured, moved them to separate module to prevent breaking changes
include Dolos::Common
# Library usage example
# Parse out a name and address from a letter
# For higher difficulty, we will not split this into multiple lines, but instead parse it all at once
letter = <<-LETTER
Mr. Vardeniui Pavardeniui
AB „Lietuvos Paštas“
Totorių g. 8
01121 Vilnius
LETTER
# Combine with 'or'
honorific = c("Mr. ") | c("Mrs. ") | c("Ms. ")
# Can be parsed any_char which will include needed letters
# Or combine LT letters with latin alphabet
alpha_with_lt = char_in("ąčęėįšųūžĄČĘĖĮŠŲŪŽ") | alpha
# Capture all letters in a row and join them,
# because they are captured as elements of array by each alpha_with_lt parser.
first_name = alpha_with_lt.rep.map(&:join).capture!
last_name = alpha_with_lt.rep.map(&:join).capture!
# Combine first line parsers
# Consume zero or more whitespace, after that honorific must follow and so on
name_line = ws.rep0 & honorific & first_name & ws & last_name & eol
# Next line is company info
# We could choose to accept UAB and AB or just AB and etc.
# 'c("AB")' is for case-sensitive string. 'string' can also be used
company_type = c("AB")
quote_open = c("„")
quote_close = c("“")
# Consume LT alphabet with whitespace
company_name = (alpha_with_lt | ws).rep.map(&:join).capture!
company_info = company_type & ws.rep0 & quote_open & company_name & quote_close
second_line = ws.rep0 & company_info & eol
# Address line
# 'char_while' will consume characters while passed predicate is true
# This could be an alternative to previous 'alpha_with_lt' approach
# After that result is captured and mapped to hash
# Mapping to hash so at the end its easy to tell tuples apart
# Also while mapping, doing some cleaning with '.strip'
street_name = char_while(->(char) { !char.match(/\d/) }).map { |s| { street: s.strip } }.capture!
building = digits.map { |s| { building: s.strip } }.capture!
address_line = ws.rep0 & street_name & building & eol
# City line
# All digits can be matched here or 'digits.rep(5)' could be used. Also joining with map.
postcode = digits.map { |s| { postcode: s.strip } }.capture!
city = alpha_with_lt.rep.map(&:join).map { |s| { city: s.strip } }.capture!
city_line = ws.rep0 & postcode & ws & city & eol
# Full letter parser which is combined from all previous parsers. All previous parsers can be ran separately.
letter_parser = name_line & second_line & address_line & city_line
result = letter_parser.run(letter)
pp result.captures
- Better error handling
- Benchmarks & parser tests
- Documentation
- Performance
bundle exec ruby benchmarks/json/json.rb
Dolos
nested json benchmark 8.426 (± 0.0%) i/s - 43.000 in 5.103600s
letter benchmark 3.145k (± 0.7%) i/s - 15.810k in 5.027961s
# Note: 23 times slower than Pure Ruby specialized json parser (below) if used to parse json
nested json 166KB bench 8.189 (± 0.0%) i/s - 41.000 in 5.007158s
nested json 1MB bench 0.959 (± 0.0%) i/s - 5.000 in 5.230650s
-----------------------------------------------------------
Pure ruby (flori/json)
nested json 1MB bench 24.213 (± 4.1%) i/s - 122.000 in 5.042309s
nested json 166KB bench 188.070 (± 1.6%) i/s - 954.000 in 5.073788s
Ruby native (C)
nested json 1MB bench 309.519 (± 0.3%) i/s - 1.560k in 5.040164s
Docsify is used to generate documentation. To run it locally:
Installation:
npm i docsify-cli -g
Run:
docsify serve docs
Contributors are welcome. Note: since library is not yet stable, I recommend getting in touch with me before starting to work on something.