let prelude = import! std.prelude
let io @ { ? } = import! std.io
let map @ { Map } = import! std.map
let { Bool } = import! std.bool
let { Option } = import! std.option
let { Result } = import! std.result
let string = import! std.string
let thread = import! std.thread
let array = import! std.array
let { ref, load, (<-) } = import! std.reference
let rustyline = import! rustyline
let { ReadlineError } = import! rustyline_types
let repl_prim = import! repl.prim
let { (<<) } = import! std.function
let { Applicative, wrap, (*>) } = import! std.applicative
let { flat_map, (>>=) } = import! std.monad
let { append = (++) } = string.semigroup
let ord_map @ { singleton, find, insert, ? } = map.make string.ord
let { (<>) } = import! std.prelude
let { empty } = ord_map.monoid
let run_interruptible_io cpu_pool action : CpuPool -> IO String -> IO (Result String String) =
do eval_thread = thread.new_thread ()
let interruptible_action = repl_prim.finish_or_interrupt cpu_pool eval_thread action
io.catch (io.functor.map Ok interruptible_action) (wrap << Err)
let load_file cpu_pool filename : CpuPool -> String -> IO String =
let last_slash =
match string.rfind filename "/" with
| None -> 0
| Some i -> i + 1
let modulename = string.slice filename last_slash (string.len filename - 3)
let action =
do expr = io.read_file_to_string filename
do result = io.load_script modulename expr
wrap result
do result = run_interruptible_io cpu_pool action
match result with
| Ok x -> wrap x
| Err x -> wrap x
let run_file cpu_pool filename : CpuPool -> String -> IO () =
let action =
do expr = io.read_file_to_string filename
do result = io.run_expr expr
wrap (result.value ++ " : " ++ result.typ)
do result = run_interruptible_io cpu_pool action
match result with
| Ok _ -> io.println ""
| Err x -> io.println x
type ReplAction = | Continue | Quit
type Cmd = { name : String, alias : String, info : String, action : String -> IO ReplAction }
type Commands = Map String Cmd
let make_commands cpu_pool : CpuPool -> Commands =
let print_result result =
match result with
| Ok x -> io.println x
| Err x -> io.println x
let commands = ref []
let cmds : Array Cmd = [{
name = "quit",
alias = "q",
info = "Quit the REPL",
// FIXME a -> IO ReplAction signature should not be necessary
action =
let x : a -> IO ReplAction = \_ -> wrap Quit
x,
}, {
name = "type",
alias = "t",
info = "Prints the type with an expression",
action =
\arg ->
repl_prim.type_of_expr arg >>= print_result
*> wrap Continue,
},
{
name = "info",
alias = "i",
info = "Prints information about the given name",
action = \arg -> repl_prim.find_info arg >>= print_result *> wrap Continue,
},
{
name = "kind",
alias = "k",
info = "Prints the kind with the given type",
action = \arg -> repl_prim.find_kind arg >>= print_result *> wrap Continue,
},
{
name = "load",
alias = "l",
info = "Loads the file at \'folder/module.ext\' and stores it at \'module\'",
action = \arg -> load_file cpu_pool arg >>= io.println *> wrap Continue,
},
{
name = "script",
alias = "s",
info = "Runs the script at `FILENAME`",
action = \arg -> run_file cpu_pool arg *> wrap Continue,
},
{
name = "help",
alias = "h",
info = "Print this help",
action = \_ ->
let print_header = io.println "Available commands\n"
let print_cmd cmd : Cmd -> IO () =
io.println (" :" ++ cmd.name ++ " (" ++ cmd.alias ++ ") " ++ cmd.info)
print_header *> array.traversable.traverse io.applicative print_cmd (load commands)
*> wrap Continue,
}]
commands <- cmds
array.foldable.foldl
(\map cmd -> singleton cmd.name cmd <> singleton cmd.alias cmd <> map)
empty
cmds
let { Parser, parse, ? } = import! std.parser
let cmd_parser : Parser { cmd : String, arg : String } =
let {
any,
recognize,
skip_many1,
token,
spaces,
letter,
monad = { flat_map },
alternative,
applicative } = import! std.parser
let { (<|>) } = import! std.applicative
let word = recognize (skip_many1 letter)
let arg_parser = recognize (skip_many1 any)
do _ = token ':'
do cmd = word
do arg = (spaces *> arg_parser) <|> wrap ""
wrap { cmd, arg }
let do_command commands line : Commands -> String -> IO ReplAction =
match parse cmd_parser line with
| Ok { cmd, arg } ->
match find cmd commands with
| Some command -> command.action arg
| None -> io.println ("Unknown command \'" ++ cmd ++ "\'") *> wrap Continue
| Err err ->
io.println "Expected a command such as `:h`"
*> wrap Continue
let store line : String -> IO ReplAction =
let line = string.trim line
match string.find line " " with
| Some bind_end ->
let binding = string.slice line 0 bind_end
let expr = string.slice line bind_end (string.len line)
io.load_script binding expr *> wrap Continue
| None -> io.println "Expected binding in definition" *> wrap Continue
type Repl = { commands : Commands, editor : Editor, cpu_pool : CpuPool }
let loop repl : Repl -> IO () =
let run_line line =
if string.is_empty (string.trim line) then
wrap Continue
else if string.starts_with line ":" then
do_command repl.commands line
else
let action =
do eval_thread = thread.new_thread ()
let eval_action = repl_prim.eval_line line
repl_prim.finish_or_interrupt repl.cpu_pool eval_thread eval_action
io.catch action wrap >>= io.println
*> wrap Continue
do line_result = rustyline.readline repl.editor "> "
match line_result with
| Err Eof -> wrap ()
| Err Interrupted -> loop repl
| Ok line ->
do continue = run_line line
match continue with
| Continue -> loop repl
| Quit ->
do _ = rustyline.save_history repl.editor
wrap ()
let run x : () -> IO () =
do _ = io.println "gluon (:h for help, :q to quit)"
do editor = rustyline.new_editor ()
do cpu_pool = repl_prim.new_cpu_pool 1
let commands = make_commands cpu_pool
let repl = { commands, editor, cpu_pool }
loop repl
run