path.lua


module("path", package.seeall)

require("tuple")
require("lfs")
require("err")
require("config")

local sep=config.dirsep

function join(p, f)
    return p..sep..f
end

function dirbasename(p)
    local d, b = string.match(p,
        "(.*)"..sep.."+([^"..sep.."]+)"..sep.."*$")
    if not b then
        return string.match(p, "([^"..sep.."]*")
    else
        return d, b
    end
end

function dirname(p)
    return tuple.fst(dirbasename(p))
end

function basename(p)
    return tuple.snd(dirbasename(p))
end

-- would rather do this as an iterator, but can't
-- coroutine.yield from gsub handler
function split(p)
    local t={}
    local head=""
    local s, p2 = string.match(p, "^("..sep.."+)(.*)$")
    if s then
        table.insert(t, "/.") -- root
        p=p2
    end
    string.gsub(p, "([^"..sep.."]+)"..sep.."+", 
            function(d) table.insert(t, d); end)
    return t
end

function parts(p)
    local s={i=1, t=split(p)}
    local function g(s)
        local v=s.t[s.i]
        s.i=s.i+1
        return v
    end
    return g, s
end

function makepath(p)
    local head=""
    for d in parts(p) do
        head=head..d
        local a=lfs.attributes(head)
        if not a then
            local success, e = lfs.mkdir(head)
            if not success then
                err.file(head, e)
            end
        elseif a.mode~="directory" then
            err.file(head, "not a directory")
        end
        head=head..sep
    end
end

--[[
print(dirbasename("/foo/bar/baz"))

for k in parts("//foo/bar/baz/quk") do
    print(k)
end

makepath("foo/bar/baz/quk")
--]]