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|
--- lam.repl
local m = {}
local read = require("read")
local eval = require("eval")
local pp = require("dump").pp
local function schemeprint (x)
-- if x == nil then return end
if x == true then
print("#t")
elseif x == false then
print("#f")
elseif x == nil then
print("#n")
else
print(x)
end
end
local lam = [[
@,,,@
<|^ ^|> l a m
| /) 0015
|I /))) acdw
-------------
]]
function m.repl (prompt, infile, out)
-- PROMPT should be a string, INFILE is a filename, and OUT is either a
-- filename, nil (in which case it will be stdout), or false (which
-- suppresses output)
local inport = read.inport(infile)
if out ~= false then
io.output(out)
io.write(lam)
end
io.output():setvbuf("line")
if prompt then
stderr = io.open("/dev/stderr", "w") -- Linux-only !
end
while true do -- loop
if prompt then
stderr:write(prompt)
stderr:flush()
end
-- read
local ok, x = xpcall(
function () return read.read(inport) end,
function (e)
local start = e:find(": ")
return e:sub(start+2)
end
)
if not ok then
print("(read) not ok: " .. x)
x = nil
end
-- eval
if x then
local ok, val =
xpcall(
function () return eval.eval(x) end,
function (e)
local start = e:find(": ")
return e:sub(start+2)
end
)
if not ok then
print("(eval) not ok: " .. val)
elseif out ~= false then
-- print
schemeprint(val)
end
end
end
inport:close()
stderr:close()
io.output():close()
end
--------
return m
|
