Hasche

/ˈhæʃ/: Haskell + Scheme

An interpreter of a subset of Scheme written in Haskell

Features

• REPL Session
• call/cc
• Non-hygienic macros

Usage

Build

$ cabal build

Run

$ cabal exec hasche -- exec programs/hello.scm
# or
$ cabal exec hasche -- repl

List of available syntax, macros & functions

Special forms

define, define-macro, set!, lambda, if, quote, quasiquote, unquote, unquote-splicing, match

Basic macros

begin, when, unless, and, or, cond, let, let*, letrec, do

Basic functions

eval, apply

null?, pair?, boolean?, number?, string?, symbol?, procedure?

not

+, -, *, /, =, <, <=, >, >=

list?, car, cdr, cons, list, length, memq, last, append, set-car!, set-cdr!, caar, cadr, cdar, cddr, map, for-each

string-append, symbol->string, string->symbol, string->number, number->string

eq?, neq?, equal?

open-input-file, open-output-file, close-input-port, close-output-port, read, display, write, newline, load

call/cc, call-with-current-continuation

gensym

Lazy evaluation

delay, force, delay-force, promise-done?

Future works

• Multiple values
• Tail call optimization
• Hygienic macro
• Exception handling