diff options
Diffstat (limited to 'types.lua')
| -rw-r--r-- | types.lua | 112 |
1 files changed, 0 insertions, 112 deletions
| diff --git a/types.lua b/types.lua deleted file mode 100644 index e4813b2..0000000 --- a/types.lua +++ /dev/null | |||
| @@ -1,112 +0,0 @@ | |||
| 1 | --- lam.types | ||
| 2 | |||
| 3 | local types = {} | ||
| 4 | local util = require "util" | ||
| 5 | table.unpack = table.unpack or unpack | ||
| 6 | |||
| 7 | --- Converting between types | ||
| 8 | |||
| 9 | types.globalns = {} -- namespace | ||
| 10 | |||
| 11 | types.Symbol = | ||
| 12 | function (name, ns, aliases) | ||
| 13 | ns = ns or types.globalns | ||
| 14 | aliases = aliases or {} | ||
| 15 | if ns[name] then return ns[name] end | ||
| 16 | local sym = { name = name, aliases = aliases } | ||
| 17 | ns[name] = sym | ||
| 18 | for _,a in ipairs(aliases) do | ||
| 19 | ns[a] = sym | ||
| 20 | end | ||
| 21 | local mt = { | ||
| 22 | __type = "Symbol", | ||
| 23 | __tostring = function (self) return self.name end, | ||
| 24 | } | ||
| 25 | return setmetatable(sym, mt) | ||
| 26 | end | ||
| 27 | |||
| 28 | types.Number = tonumber | ||
| 29 | |||
| 30 | types.String = | ||
| 31 | function (str) | ||
| 32 | local s = { | ||
| 33 | value = str, | ||
| 34 | escape = | ||
| 35 | function(self) | ||
| 36 | return self:gsub("\"", "\\\"") | ||
| 37 | end, | ||
| 38 | } | ||
| 39 | local mt = { | ||
| 40 | __type = "String", | ||
| 41 | __tostring = | ||
| 42 | function (self) | ||
| 43 | return string.format( | ||
| 44 | "\"%s\"", | ||
| 45 | self:escape()) | ||
| 46 | end, | ||
| 47 | } | ||
| 48 | return setmetatable(s, mt) | ||
| 49 | end | ||
| 50 | |||
| 51 | types.Cons = | ||
| 52 | function (a, b) | ||
| 53 | assert(a ~= nil and b ~= nil, | ||
| 54 | "Need two non-nil arguments in a pair") | ||
| 55 | local s = { a, b } | ||
| 56 | local mt = { | ||
| 57 | __type = "Pair", | ||
| 58 | __tostring = | ||
| 59 | function (p) | ||
| 60 | local out = {} | ||
| 61 | local car, cdr = p[1], p[2] | ||
| 62 | while cdr do | ||
| 63 | table.insert(out, tostring(car)) | ||
| 64 | if type(cdr) == "table" then | ||
| 65 | car = cdr[1] | ||
| 66 | cdr = cdr[2] | ||
| 67 | else | ||
| 68 | table.insert(out, ".") | ||
| 69 | table.insert(out, cdr) | ||
| 70 | break | ||
| 71 | end | ||
| 72 | end | ||
| 73 | return "("..table.concat(out, " ")..")" | ||
| 74 | end | ||
| 75 | |||
| 76 | } | ||
| 77 | return setmetatable(s, mt) | ||
| 78 | end | ||
| 79 | |||
| 80 | types.List = | ||
| 81 | function (tbl) | ||
| 82 | local function tolist(base, items) | ||
| 83 | if #items == 0 then return base end | ||
| 84 | return tolist( | ||
| 85 | types.Cons(table.remove(items), base), | ||
| 86 | items) | ||
| 87 | end | ||
| 88 | return tolist({}, tbl) | ||
| 89 | end | ||
| 90 | |||
| 91 | --- Determining types | ||
| 92 | |||
| 93 | types.lamtype = | ||
| 94 | function (x) | ||
| 95 | if type(x) == "number" then | ||
| 96 | return "Number" | ||
| 97 | elseif getmetatable(x) and getmetatable(x).__type then | ||
| 98 | return getmetatable(x).__type | ||
| 99 | else | ||
| 100 | return type(x) | ||
| 101 | end | ||
| 102 | end | ||
| 103 | |||
| 104 | --- Type predicates | ||
| 105 | |||
| 106 | types.isa = | ||
| 107 | function (x, t) | ||
| 108 | return types.lamtype(x) == t | ||
| 109 | end | ||
| 110 | |||
| 111 | --- | ||
| 112 | return types | ||