mvoe implementations into subdirs

1 files changed, 0 insertions, 128 deletions

diff --git a/minimal.jl b/minimal.jl
deleted file mode 100644
index 303b87a..0000000
--- a/minimal.jl
+++ /dev/null
@@ -1,128 +0,0 @@
-
-# A partial Scheme implementation in Julia
-
-#   null -> nothing
-#   pair -> Pair type
-#   boolean (true/false) -> true/false
-#   number -> Number
-#   identifier/symbol -> symbol
-
-is_atom(x) = x == () || !(x == nothing ||
-                          typeof(x) <: Tuple ||
-                          typeof(x) <: Array ||
-                          typeof(x) <: Dict)
-is_null(x) = x == ()
-is_zero(x) = x == 0
-is_eq(a, b) = a == b
-is_number(x) = typeof(x) <: Number
-is_boolean(x) = x == true || x == false
-is_builtin(x) = x in (:lambda, :quote, :cond, :else, :cons, :car, :cdr,
-                      :isnull, :iseq, :isatom, :iszero, :isnumber,
-                      :+, :-, :*, :/, +, -, *, /)
-
-identity_action(x, ctx) = x
-lookup_action(x, ctx) = ctx[x]
-quote_action(x, ctx) = length(x) == 2 ? x[2] : throw(ErrorException())
-
-function cond_action(x, ctx)
-    for line in x[2:end]
-        if line[1] == :else
-            return meaning(line[2], ctx)
-        elseif meaning(line[1], ctx)
-            return meaning(line[2], ctx)
-        else
-            # "unspecified"
-            return nothing
-        end
-    end
-end
-
-function lambda_action(x, ctx)
-    return (:procedure, x[2], x[3:end], copy(ctx))
-end
-
-function apply_action(x, ctx)
-    if is_builtin(x[1])
-        action = x[1]
-        args = [meaning(y, ctx) for y in x[2:end]]
-        if action == :cons
-            return tuple(args[1], args[2])
-        elseif action == :car
-            return args[1][1]
-        elseif action == :cdr
-            return args[1][2]
-        elseif action == :isnull
-            return is_null(args[1])
-        elseif action == :iseq
-            return is_eq(args[1], args[2])
-        elseif action == :isatom
-            return is_atom(args[1])
-        elseif action == :iszero
-            return is_zero(args[1])
-        elseif action == :isnumber
-            return is_number(args[1])
-        elseif action == :+ || action == +
-            return args[1] + args[2]
-        elseif action == :- || action == -
-            return args[1] - args[2]
-        elseif action == :* || action == *
-            return args[1] * args[2]
-        elseif action == :/ || action == /
-            return args[1] / args[2]
-        else
-            throw(ErrorException("Unexpected builtin: $(x[0])"))
-        end
-    elseif typeof(x[1]) <: Tuple
-        proc = meaning(x[1], ctx)
-        if proc[1] != :procedure
-            throw(ErrorException("Not applicable: $(str(proc))"))
-        end
-        variables = proc[2]
-        body = proc[3]
-        closure = copy(proc[4])
-        args = [meaning(y, ctx) for y in x[2:end]]
-        for i in 1:length(variables)
-            closure[variables[i]] = args[i]
-        end
-        ret = nothing
-        for expr in body
-            ret = meaning(expr, closure)
-        end
-        return ret
-    else
-        throw(ErrorException("Unexpected... thing...: $(x[1])"))
-    end
-end
-
-function meaning(x, ctx)
-    action = nothing
-    if is_atom(x)
-        if is_number(x) || is_boolean(x) || is_builtin(x)
-            return identity_action(x, ctx)
-        elseif typeof(x) <: Symbol
-            return lookup_action(x, ctx)
-        end
-    elseif typeof(x) <: Tuple
-        if x[1] == :quote
-            return quote_action(x, ctx)
-        elseif x[1] == :cond
-            return cond_action(x, ctx)
-        elseif x[1] == :lambda
-            return lambda_action(x, ctx)
-        elseif typeof(x[1]) <: Tuple
-            return apply_action(x, ctx)
-        else   # some other identifier, either builtin or not
-            return apply_action(x, ctx)
-        end
-    end
-    throw(ErrorException("Unexpected expression: $x"))
-end
-
-function value(ast)
-    return meaning(ast, Dict())
-end
-
-function test_minimal_scheme()
-    @assert 6 == value( ((:lambda, (:x, ), (+, 1, :x)), 5) )
-    value( (:car, (:quote, (1, 2, 3, 4))) )
-end