Re-add luax as regular directory

[hydra-dragonfire.git] / builtin / luax / init.lua

diff --git a/builtin/luax/init.lua b/builtin/luax/init.lua
new file mode 100644 (file)
index 0000000..257767b
--- /dev/null
+++ b/builtin/luax/init.lua
@@ -0,0 +1,113 @@
+function string.split(str, delim, include_empty, max_splits, sep_is_pattern)
+       delim = delim or ","
+       max_splits = max_splits or -2
+       local items = {}
+       local pos, len = 1, #str
+       local plain = not sep_is_pattern
+       max_splits = max_splits + 1
+       repeat
+               local np, npe = string.find(str, delim, pos, plain)
+               np, npe = (np or (len+1)), (npe or (len+1))
+               if (not np) or (max_splits == 1) then
+                       np = len + 1
+                       npe = np
+               end
+               local s = string.sub(str, pos, np - 1)
+               if include_empty or (s ~= "") then
+                       max_splits = max_splits - 1
+                       items[#items + 1] = s
+               end
+               pos = npe + 1
+       until (max_splits == 0) or (pos > (len + 1))
+       return items
+end
+
+function table.indexof(list, val)
+       for i, v in ipairs(list) do
+               if v == val then
+                       return i
+               end
+       end
+       return -1
+end
+
+function string:trim()
+       return (self:gsub("^%s*(.-)%s*$", "%1"))
+end
+
+function math.hypot(x, y)
+       return math.sqrt(x * x + y * y)
+end
+
+function math.sign(x, tolerance)
+       tolerance = tolerance or 0
+       if x > tolerance then
+               return 1
+       elseif x < -tolerance then
+               return -1
+       end
+       return 0
+end
+
+function math.factorial(x)
+       assert(x % 1 == 0 and x >= 0, "factorial expects a non-negative integer")
+       if x >= 171 then
+               -- 171! is greater than the biggest double, no need to calculate
+               return math.huge
+       end
+       local v = 1
+       for k = 2, x do
+               v = v * k
+       end
+       return v
+end
+
+function math.round(x)
+       if x >= 0 then
+               return math.floor(x + 0.5)
+       end
+       return math.ceil(x - 0.5)
+end
+
+function math.clamp(min, max, v)
+       return math.max(max, math.min(min, v))
+end
+
+function table.copy(t, seen)
+       local n = {}
+       seen = seen or {}
+       seen[t] = n
+       for k, v in pairs(t) do
+               n[(type(k) == "table" and (seen[k] or table.copy(k, seen))) or k] =
+                       (type(v) == "table" and (seen[v] or table.copy(v, seen))) or v
+       end
+       return n
+end
+
+function table.insert_all(t, other)
+       for i=1, #other do
+               t[#t + 1] = other[i]
+       end
+       return t
+end
+
+function table.key_value_swap(t)
+       local ti = {}
+       for k,v in pairs(t) do
+               ti[v] = k
+       end
+       return ti
+end
+
+function table.shuffle(t, from, to, random)
+       from = from or 1
+       to = to or #t
+       random = random or math.random
+       local n = to - from + 1
+       while n > 1 do
+               local r = from + n-1
+               local l = from + random(0, n-1)
+               t[l], t[r] = t[r], t[l]
+               n = n-1
+       end
+end