[modified] moved append and append_inplace from functional to tablex

This commit is contained in:
Max Cahill 2020-04-08 20:50:51 +10:00
parent e1f759cb90
commit 8d5da0a9ff
2 changed files with 58 additions and 33 deletions

View File

@ -126,22 +126,6 @@ function functional.dedupe(t)
end)
end
--append sequence t2 into t1, modifying t1
function functional.append_inplace(t1, t2)
for i,v in ipairs(t2) do
table.insert(t1, v)
end
return t1
end
--return a new sequence with the elements of both t1 and t2
function functional.append(t1, t2)
local r = {}
functional.append_inplace(r, t1)
functional.append_inplace(r, t2)
return r
end
-----------------------------------------------------------
--common queries and reductions
-----------------------------------------------------------
@ -278,8 +262,8 @@ functional.find_best = functional.find_max
--return the element of the table that results in the value nearest to the passed value
--todo: optimise as this generates a closure each time
function functional.find_nearest(t, f, v)
return functional.find_best(t, function(e)
return -math.abs(f(e) - v)
return functional.find_min(t, function(e)
return math.abs(f(e) - v)
end)
end

View File

@ -127,22 +127,36 @@ function tablex.values(t)
return r
end
--append sequence t2 into t1, modifying t1
function tablex.append_inplace(t1, t2)
for i,v in ipairs(t2) do
table.insert(t1, v)
end
return t1
end
--return a new sequence with the elements of both t1 and t2
function tablex.append(t1, t2)
local r = {}
tablex.append_inplace(r, t1)
tablex.append_inplace(r, t2)
return r
end
--(might already exist depending on luajit)
if tablex.clear == nil then
if tablex ~= table and table.clear then
--import from global if it exists
tablex.clear = table.clear
else
--remove all values from a table
--useful when multiple references are floating around
--so you cannot just pop a new table out of nowhere
function tablex.clear(t)
assert(type(t) == "table", "table.clear - argument 't' must be a table")
local k = next(t)
while k ~= nil do
t[k] = nil
k = next(t)
end
if table.clear then
--import from global if it exists
tablex.clear = table.clear
else
--remove all values from a table
--useful when multiple references are being held
--so you cannot just create a new table
function tablex.clear(t)
assert(type(t) == "table", "table.clear - argument 't' must be a table")
local k = next(t)
while k ~= nil do
t[k] = nil
k = next(t)
end
end
end
@ -198,6 +212,33 @@ function tablex.overlay(to, from)
return to
end
--turn a table into a vaguely easy to read string
--which is also able to be parsed by lua in most cases
function tablex.stringify(t)
if type(t) ~= "table" then
return tostring(t)
end
local chunks = {}
local seen = {}
--sequential part first
for i, v in ipairs(t) do
seen[i] = true
table.insert(chunks, tablex.stringify(v))
end
--non sequential follows
for k, v in pairs(t) do
if not seen[k] then
--encapsulate anything that's not a string
--todo: also keywords
if type(k) ~= "string" then
k = "[" .. tostring(k) .. "]"
end
table.insert(chunks, k .. " = " .. tablex.stringify(v))
end
end
return "{" .. table.concat(chunks, ", ") .. "}"
end
--faster unpacking for known-length tables up to 8
--gets around nyi in luajit
--note: you can use a larger unpack than you need as the rest