Version 2.2.0

README.md

@@ -74,6 +74,38 @@ lume.weightedchoice({ ["cat"] = 10, ["dog"] = 5, ["frog"] = 0 })
 -- Returns either "cat" or "dog" with "cat" being twice as likely to be chosen.
 ```
 
+### lume.push(t, ...)
+Pushes all the given values to the end of the table `t` and returns the pushed
+values. Nil values are ignored.
+```lua
+local t = { 1, 2, 3 }
+lume.push(t, 4, 5) -- `t` becomes { 1, 2, 3, 4, 5 }
+```
+
+### lume.remove(t, x)
+Removes the first instance of the value `x` if it exists in the table `t`.
+Returns `x`.
+```lua
+local t = { 1, 2, 3 }
+lume.remove(t, 2) -- `t` becomes { 1, 3 }
+```
+
+### lume.clear(t)
+Nils all the values in the table `t`, this renders the table empty. Returns
+`t`.
+```lua
+local t = { 1, 2, 3 }
+lume.clear(t) -- `t` becomes {}
+```
+
+### lume.extend(t, ...)
+Copies all the fields from the source tables to the table `t` and returns `t`.
+If a key exists in multiple tables the right-most table's value is used.
+```lua
+local t = { a = 1, b = 2 }
+lume.extend(t, { b = 4, c = 6 }) -- `t` becomes { a = 1, b = 4, c = 6 }
+```
+
 ### lume.shuffle(t)
 Returns a shuffled copy of the array `t`.
 
@@ -149,6 +181,14 @@ an array and retains its original keys.
 lume.filter({1, 2, 3, 4}, function(x) return x % 2 == 0 end) -- Returns {2, 4}
 ```
 
+### lume.reject(t, fn [, retainkeys])
+The opposite of `lume.filter()`: Calls `fn` on each value of `t` table; returns
+a new table with only the values where `fn` returned false. If `retainkeys` is
+true the table is not treated as an array and retains its original keys.
+```lua
+lume.reject({1, 2, 3, 4}, function(x) return x % 2 == 0 end) -- Returns {1, 3}
+```
+
 ### lume.merge(...)
 Returns a new table with all the given tables merged together. If a key exists
 in multiple tables the right-most table's value is used.
@@ -212,6 +252,12 @@ values the keys.
 lume.invert({a = "x", b = "y"}) -- returns {x = "a", y = "b"}
 ```
 
+### lume.pick(t, ...)
+Returns a copy of the table filtered to only contain values for the given keys.
+```lua
+lume.pick({ a = 1, b = 2, c = 3 }, "a", "c") -- Returns { a = 1, c = 3 }
+```
+
 ### lume.keys(t)
 Returns an array containing each key of the table.
 
@@ -372,6 +418,17 @@ for i, v in lume.ripairs({ "a", "b", "c" }) do
 end
 ```
 
+### lume.color(str [, mul])
+Takes color string `str` and returns 4 values, one for each color channel (`r`,
+`g`, `b` and `a`). By default the returned values are between 0 and 1; the
+values are multiplied by the number `mul` if it is provided.
+```lua
+lume.color("#ff0000")               -- Returns 1, 0, 0, 1
+lume.color("rgba(255, 0, 255, .5)") -- Returns 1, 0, 1, .5
+lume.color("#00ffff", 256)          -- Returns 0, 256, 256, 256
+lume.color("rgb(255, 0, 0)", 256)   -- Returns 256, 0, 0, 256
+```
+
 ### lume.rgba(color)
 Takes the 32bit integer `color` argument and returns 4 numbers, one for each
 channel, with a range of 0 - 255. The returned values can be used as the
@@ -396,6 +453,36 @@ as calling `lume.chain()`.
 lume({1, 2, 3}):each(print) -- Prints 1, 2 then 3 on separate lines
 ```
 
+## Iteratee functions
+Several lume functions allow a `table`, `string` or `nil` to be used in place
+of their iteratee function argument. The functions that provide this behaviour
+are: `map()`, `all()`, `any()`, `filter()`, `reject()`, `match()` and
+`count()`.
+
+If the argument is `nil` then each value will return itself.
+```lua
+lume.filter({ true, true, false, true }, nil) -- { true, true, true }
+```
+
+If the argument is a `string` then each value will be assumed to be a table,
+and will return the value of the key which matches the string.
+``` lua
+local t = {{ z = "cat" }, { z = "dog" }, { z = "owl" }}
+lume.map(t, "z") -- Returns { "cat", "dog", "owl" }
+```
+
+If the argument is a `table` then each value will return `true` or `false`,
+depending on whether the values at each of the table's keys match the
+collection's value's values.
+```lua
+local t = {
+  { age = 10, type = "cat" },
+  { age = 8,  type = "dog" },
+  { age = 10, type = "owl" },
+}
+lume.count(t, { age = 10 }) -- returns 2
+```
+
 
 ## License
 

lume.lua

@@ -1,13 +1,13 @@
 --
 -- lume
 --
--- Copyright (c) 2015, rxi
+-- Copyright (c) 2015 rxi
 --
 -- This library is free software; you can redistribute it and/or modify it
 -- under the terms of the MIT license. See LICENSE for details.
 --
 
-local lume = { _version = "2.0.0" }
+local lume = { _version = "2.2.0" }
 
 local pairs, ipairs = pairs, ipairs
 local type, assert, unpack = type, assert, unpack or table.unpack
@@ -43,21 +43,16 @@ local iscallable = function(x)
 end
 
 local isarray = function(x)
-  return (x and x[1]) and true or false
-end
-
-local iternil = function()
-  return noop
+  return (type(x) == "table" and x[1] ~= nil) and true or false
 end
 
 local getiter = function(x)
-  if x == nil then
-    return iternil
-  elseif isarray(x) then
+  if isarray(x) then
     return ipairs
-  else
+  elseif type(x) == "table" then
     return pairs
   end
+  error("expected table", 3)
 end
 
 local iteratee = function(x)
@@ -83,7 +78,7 @@ end
 
 function lume.round(x, increment)
   if increment then return lume.round(x / increment) * increment end
-  return x > 0 and math_floor(x + .5) or math_ceil(x - .5)
+  return x >= 0 and math_floor(x + .5) or math_ceil(x - .5)
 end
 
 
@@ -149,6 +144,54 @@ function lume.weightedchoice(t)
 end
 
 
+function lume.push(t, ...)
+  local n = select("#", ...)
+  for i = 1, n do
+    t[#t + 1] = select(i, ...)
+  end
+  return ...
+end
+
+
+function lume.remove(t, x) 
+  local iter = getiter(t)
+  for i, v in iter(t) do
+    if v == x then
+      if isarray(t) then
+        table.remove(t, i)
+        break
+      else
+        t[i] = nil
+        break
+      end
+    end
+  end
+  return x
+end
+
+
+function lume.clear(t)
+  local iter = getiter(t)
+  for k, v in iter(t) do
+    t[k] = nil
+  end
+  return t
+end
+
+
+function lume.extend(t, ...)
+  for i = 1, select("#", ...) do
+    local x = select(i, ...)
+    if x then
+      for k, v in pairs(x) do
+        t[k] = v
+      end
+    end
+  end
+  return t
+end
+
+
 function lume.shuffle(t)
   local rtn = {}
   for i = 1, #t do
@@ -225,9 +268,18 @@ end
 
 
 function lume.reduce(t, fn, first)
-  local acc = first or t[1]
-  assert(acc, "reduce of an empty array with no first value")
-  for i = first and 1 or 2, #t do acc = fn(acc, t[i]) end
+  local acc = first
+  local started = first and true or false
+  local iter = getiter(t)
+  for k, v in iter(t) do
+    if started then
+      acc = fn(acc, v)
+    else
+      acc = v
+      started = true
+    end
+  end
+  assert(started, "reduce of an empty table with no first value")
   return acc
 end
 
@@ -245,8 +297,31 @@ function lume.filter(t, fn, retainkeys)
   fn = iteratee(fn)
   local iter = getiter(t)
   local rtn = {}
-  for k, v in iter(t) do
-    if fn(v) then rtn[retainkeys and k or (#rtn + 1)] = v end
+  if retainkeys then
+    for k, v in iter(t) do
+      if fn(v) then rtn[k] = v end
+    end
+  else
+    for k, v in iter(t) do
+      if fn(v) then rtn[#rtn + 1] = v end
+    end
+  end
+  return rtn
+end
+
+
+function lume.reject(t, fn, retainkeys)
+  fn = iteratee(fn)
+  local iter = getiter(t)
+  local rtn = {}
+  if retainkeys then
+    for k, v in iter(t) do
+      if not fn(v) then rtn[k] = v end
+    end
+  else
+    for k, v in iter(t) do
+      if not fn(v) then rtn[#rtn + 1] = v end
+    end
   end
   return rtn
 end
@@ -269,9 +344,11 @@ function lume.concat(...)
   local rtn = {}
   for i = 1, select("#", ...) do
     local t = select(i, ...)
-    local iter = getiter(t)
-    for k, v in iter(t) do
-      rtn[#rtn + 1] = v
+    if t ~= nil then
+      local iter = getiter(t)
+      for k, v in iter(t) do
+        rtn[#rtn + 1] = v
+      end
     end
   end
   return rtn
@@ -345,6 +422,16 @@ function lume.invert(t)
 end
 
 
+function lume.pick(t, ...)
+  local rtn = {}
+  for i = 1, select("#", ...) do
+    local k = select(i, ...)
+    rtn[k] = t[k]
+  end
+  return rtn
+end
+
+
 function lume.keys(t)
   local rtn = {}
   local iter = getiter(t)
@@ -400,8 +487,16 @@ end
 
 
 function lume.combine(...)
+  local n = select('#', ...)
+  if n == 0 then return noop end
+  if n == 1 then 
+    local fn = select(1, ...)
+    if not fn then return noop end
+    assert(iscallable(fn), "expected a function or nil")
+    return fn
+  end
   local funcs = {}
-  for i = 1, select("#", ...) do
+  for i = 1, n do
     local fn = select(i, ...)
     if fn ~= nil then
       assert(iscallable(fn), "expected a function or nil")
@@ -489,20 +584,26 @@ function lume.wordwrap(str, limit)
     check = limit
   end
   local rtn = {}
-  for j, line in ipairs(lume.split(str, "\n")) do
-    local str
-    for i, word in ipairs(lume.split(line)) do
-      local s = (str and (str .. " ") or "") .. word
-      if check(s) then
-        rtn[#rtn + 1] = str
-        str = word
+  local line = ""
+  for word, spaces in str:gmatch("(%S+)(%s*)") do
+    local str = line .. word
+    if check(str) then
+      table.insert(rtn, line .. "\n")
+      line = word
+    else
+      line = str
+    end
+    for c in spaces:gmatch(".") do
+      if c == "\n" then
+        table.insert(rtn, line .. "\n")
+        line = ""
       else
-        str = s
+        line = line .. c
       end
     end
-    rtn[#rtn + 1] = str
   end
-  return table.concat(rtn, "\n")
+  table.insert(rtn, line)
+  return table.concat(rtn)
 end
 
 
@@ -587,13 +688,32 @@ local ripairs_iter = function(t, i)
 end
 
 function lume.ripairs(t)
-  if t == nil then
-    return noop
-  end
   return ripairs_iter, t, (#t + 1)
 end
 
 
+function lume.color(str, mul)
+  mul = mul or 1
+  local r, g, b, a
+  r, g, b = str:match("#(%x%x)(%x%x)(%x%x)")
+  if r then
+    r = tonumber(r, 16) / 0xff
+    g = tonumber(g, 16) / 0xff
+    b = tonumber(b, 16) / 0xff
+    a = 1
+  elseif str:match("rgba?%s*%([%d%s%.,]+%)") then
+    local f = str:gmatch("[%d.]+")
+    r = (f() or 0) / 0xff
+    g = (f() or 0) / 0xff
+    b = (f() or 0) / 0xff
+    a = f() or 1
+  else
+    error(("bad color string '%s'"):format(str))
+  end
+  return r * mul, g * mul, b * mul, a * mul
+end
+
+
 function lume.rgba(color)
   local a = math_floor((color / 16777216) % 256)
   local r = math_floor((color /    65536) % 256)

test/test_lume.lua

@@ -106,6 +106,55 @@ tests["lume.weightedchoice"] = function()
   tester.test.error( lume.weightedchoice, { a = 1, b = -1 }   )
 end
 
+-- lume.push
+tests["lume.push"] = function()
+  local t = { 1, 2 }
+  lume.push(t, 3, 4)
+  testeq(t, { 1, 2, 3, 4 })
+  lume.push(t, 5, nil, 6, nil, 7)
+  testeq(t, { 1, 2, 3, 4, 5, 6, 7 })
+  lume.push(t)
+  testeq(t, { 1, 2, 3, 4, 5, 6, 7 })
+  local x, y = lume.push(t, 123, 456)
+  testeq(x, 123)
+  testeq(y, 456)
+end
+
+-- lume.remove
+tests["lume.remove"] = function()
+  local t = { 1, 2, 3, 4, 5 }
+  lume.remove(t, 3)
+  testeq(t, { 1, 2, 4, 5  })
+  lume.remove(t, 1)
+  testeq(t, { 2, 4, 5 })
+  lume.remove(t, 5)
+  testeq(t, { 2, 4 })
+  local m = { a = 1, b = 2, c = 3 }
+  local x = lume.remove(t, 123)
+  testeq(x, 123)
+end
+
+-- lume.clear
+tests["lume.clear"] = function()
+  local t = { 1, 2, 3 }
+  lume.clear(t)
+  testeq(t, {})
+  local m = { a = 1, b = 2, c = 3 }
+  lume.clear(m)
+  testeq(m, {})
+  testeq( lume.clear(t) == t, true )
+end
+
+-- lume.extend
+tests["lume.extend"] = function()
+  local t = { a = 10, b = 20, c = 30 }
+  testeq( lume.extend(t) == t, true )
+  lume.extend(t, { d = 40 }, { e = 50 })
+  testeq( t, { a = 10, b = 20, c = 30, d = 40, e = 50 } )
+  lume.extend(t, { a = "cat", b = "dog" }, { b = "owl", c = "fox" })
+  testeq( t, { a = "cat", b = "owl", c = "fox", d = 40, e = 50 } )
+end
+
 -- lume.shuffle
 tests["lume.shuffle"] = function()
   local t = {1, 2, 3, 4, 5}
@@ -191,6 +240,9 @@ tests["lume.reduce"] = function()
   testeq( lume.reduce({1, 2, 3, 4}, add, 5),          15          )
   testeq( lume.reduce({1}, add),                      1           )
   testeq( lume.reduce({}, concat, "potato"),          "potato"    )
+  testeq( lume.reduce({a=1, b=2}, add, 5),            8           )
+  testeq( lume.reduce({a=1, b=2}, add),               3           )
+  tester.test.error(lume.reduce, {}, add)
 end
 
 -- lume.set
@@ -214,6 +266,16 @@ tests["lume.filter"] = function()
   testeq( t, {{ x=1, y=1 }, {x=1, y=3}} )
 end
 
+-- lume.reject
+tests["lume.reject"] = function()
+  local t = lume.reject({1, 2, 3, 4, 5}, function(x) return x % 2 == 0 end  ) 
+  testeq( t, {1, 3, 5} )
+  local t = lume.reject({a=1, b=2, c=3}, function(x) return x == 2 end, true) 
+  testeq( t, {a=1, c=3} )
+  local t = lume.reject({{ x=1, y=1 }, { x=2, y=2 }, { x=1, y=3 }}, { x = 1 })
+  testeq( t, {{ x=2, y=2 }} )
+end
+
 -- lume.merge
 tests["lume.merge"] = function()
   testeq( lume.merge(),                       {}              )
@@ -311,6 +373,15 @@ tests["lume.invert"] = function()
   testeq( lume.invert(lume.invert{a = 1, b = 2}), {a = 1, b = 2}      )
 end
 
+-- lume.pick
+tests["lume.pick"] = function()
+  local t = { cat = 10, dog = 20, fox = 30, owl = 40 }
+  testeq( lume.pick(t, "cat", "dog"), { cat = 10, dog = 20 } )
+  testeq( lume.pick(t, "fox", "owl"), { fox = 30, owl = 40 } )
+  testeq( lume.pick(t, "owl"), { owl = 40 } )
+  testeq( lume.pick(t), {} )
+end
+
 -- lume.keys
 tests["lume.keys"] = function()
   testeq( lume.keys({}), {} )
@@ -370,6 +441,12 @@ tests["lume.combine"] = function()
   fn = lume.combine(nil, a, nil, b, nil)
   fn(10, 20)
   testeq( acc, 230 )
+  local x = false
+  fn = lume.combine(function() x = true end)
+  fn()
+  testeq( x, true )
+  testeq( type(lume.combine(nil)), "function" )
+  testeq( type(lume.combine()),    "function" )
 end
 
 -- lume.call
@@ -433,8 +510,8 @@ end
 
 -- lume.wordwrap
 tests["lume.wordwrap"] = function()
-  local str = "A small string with some words and then some more words"
-  local b = "A small string with\nsome words and then\nsome more words"
+  local str = "A small string with some words and then some more   words"
+  local b = "A small string with \nsome words and then \nsome more   words"
   local fn = function(str) return #str >= 20 end
   testeq( lume.wordwrap(str),     str )
   testeq( lume.wordwrap(str, 20), b   )
@@ -494,8 +571,24 @@ tests["lume.ripairs"] = function()
     table.insert(r, { i, v })
   end
   testeq( r, { { 3, "c" }, { 2, "b" }, { 1, "a" } })
-  for i, v in lume.ripairs(nil) do
-  end
+  tester.test.error(lume.ripairs, nil)
+end
+
+-- lume.color
+tests["lume.color"] = function()
+  testeq({ lume.color("#ff0000") },                   { 1, 0, 0, 1 }  )
+  testeq({ lume.color("#00ff00") },                   { 0, 1, 0, 1 }  )
+  testeq({ lume.color("#0000ff") },                   { 0, 0, 1, 1 }  )
+  testeq({ lume.color("rgb( 255, 255, 255 )") },      { 1, 1, 1, 1 }  )
+  testeq({ lume.color("rgb (0, 0, 0)") },             { 0, 0, 0, 1 }  )
+  testeq({ lume.color("rgba(255, 255, 255, .5)") },   { 1, 1, 1, .5 } )
+  testeq({ lume.color("#ffffff", 2) },                { 2, 2, 2, 2 }  )
+  testeq({ lume.color("rgba(255, 255, 255, 1)", 3) }, { 3, 3, 3, 3 }  )
+  tester.test.error(lume.color, "#ff00f")
+  tester.test.error(lume.color, "#xyzxyz")
+  tester.test.error(lume.color, "rgba(hello)")
+  tester.test.error(lume.color, "rgba()")
+  tester.test.error(lume.color, "rgba(1, 1, 1, 1")
 end
 
 -- lume.rgba