Is there a way to convert or create a new [[bracket style string]] based on an existing 'quote style string'?
s = "one\ntwo" -- how the string was created
s2 = [[one\ntwo]] -- what i want the new string to be
Escaping the escape sequence seems to achieve the desired effect, at least in this case.
s2 = string.gsub(s, "\n", "\\n")
> print(s2)
one\ntwo
One way is to make a table that has all the possible escape sequences:
local t = {["\a"] = [[\a]],
["\b"] = [[\b]],
["\f"] = [[\f]],
["\n"] = [[\n]],
["\r"] = [[\r]],
["\t"] = [[\t]],
["\r"] = [[\r]],
["\\"] = [[\\]],
["\""] = [["]],
["\'"] = [[']],
}
local s2 = s:gsub(".", t)
Related
have a data like this
result = {
[1] = { ["identifier"] = MMK18495,["vehicles"] = {"vehN":"Caracara 4x4","vehM":"caracara2","totals":3},["id"] = 1,} ,
[2] = { ["identifier"] = MMK18495,["vehicles"] = {"vehN":"Sandking SWB","vehM":"sandking2","totals":3},["id"] = 2,} ,
[3] = { ["identifier"] = MMK18495,["vehicles"] = {"totals":5,"vehN":"Caracara 4x4","vehM":"caracara2"},["id"] = 3,} ,
}
trying to sort this data to a menu like this
for i=1, #result, 1 do
local ownedcars = result[i].vehicles
print(dump(ownedcars))
for _,v in pairs(ownedcars) do -- <- the error is here
menu[#menu+1] = {
header = " Model "..v.vehM.." Name "..v.vehN.." quantity"..v.totals,
txt = "",
}
end
end
the output of ownedcars
{"vehN":"Caracara 4x4","vehM":"caracara2","totals":3}
but here is the error
As others have commented, this is not a Lua table. When inputting JSON tables, Lua reads them as strings. You will first need to convert your given JSON string into Lua. Thankfully, others have already done this. I will refer you to this question which has answers that solved this problem.
Once you've converted your JSON string to a Lua table, you should be good to go.
Hello I am trying to get some data from a text file and put it into a table.
Im not sure how to add more then one pattern while also doing what I want, I know this pattern by its self %a+ finds letters and %b{} finds brackets, but I am not sure how to combine them together so that I find the letters as a key and the brackets as a value and have them be put into a table that I could use.
text file :
left = {{0,63},{16,63},{32,63},{48,63}}
right = {{0,21},{16,21},{32,21},{48,21}}
up = {{0,42},{16,42},{32,42},{48,42}}
down = {{0,0},{16,0},{32,0},{48,0}}
code:
local function get_animations(file_path)
local animation_table = {}
local file = io.open(file_path,"r")
local contents = file:read("*a")
for k, v in string.gmatch(contents, ("(%a+)=(%b{})")) do -- A gets words and %b{} finds brackets
animation_table[k] = v
print("key : " .. k.. " Value : ".. v)
end
file:close()
end
get_animations("Sprites/Player/MainPlayer.txt")
This is valid Lua code, why not simply execute it?
left = {{0,63},{16,63},{32,63},{48,63}}
right = {{0,21},{16,21},{32,21},{48,21}}
up = {{0,42},{16,42},{32,42},{48,42}}
down = {{0,0},{16,0},{32,0},{48,0}}
If you don't want the data in globals, use the string library to turn it into
return {
left = {{0,63},{16,63},{32,63},{48,63}},
right = {{0,21},{16,21},{32,21},{48,21}},
up = {{0,42},{16,42},{32,42},{48,42}},
down = {{0,0},{16,0},{32,0},{48,0}},
}
befor you execute it.
If you insist on parsing that file you can use a something like this for each line:
local line = "left = {{0,63},{16,63},{32,63},{48,63}}"
print(line:match("^%w+"))
for num1, num2 in a:gmatch("(%d+),(%d+)") do
print(num1, num2)
end
This should be enough to get you started. Of course you wouldn't print those values but put them into a table.
I have something like
str = "What a wonderful string //011// this is"
I have to replace the //011// with something like convertToRoman(011) and then get
str = "What a wonderful string XI this is"
However, the conversion into roman numbers is no problem here.
It is also possible that the string str didn't has a //...//. In this case it should simply return the same string.
function convertSTR(str)
if not string.find(str,"//") then
return str
else
replace //...// with convertToRoman(...)
end
return str
end
I know that I can use string.find to get the complete \\...\\ sequence. Is there an easier solution with pattern matching or something similiar?
string.gsub accepts a function as a replacement. So, this should work
new = str:gsub("//(.-)//", convertToRoman)
I like LPEG, therefore here is a solution with LPEG:
local lpeg = require"lpeg"
local C, Ct, P, R = lpeg.C, lpeg.Ct, lpeg.P, lpeg.R
local convert = function(x)
return "ROMAN"
end
local slashed = P"//" * (R("09")^1 / convert) * P"//"
local other = C((1 - slashed)^0)
local grammar = Ct(other * (slashed * other)^0)
print(table.concat(grammar:match("What a wonderful string //011// this is"),""))
I have a lua string in Chinese, such as
str = '这是一个中文字符串' -- in English: 'this is a Chinese string'
Now I would like to iterate the string above, to get the following result:
str[1] = '这'
str[2] = '是'
str[3] = '一'
str[4] = '个'
str[5] = '中'
str[6] = '文'
str[7] = '字'
str[8] = '符'
str[9] = '串'
and also output 9 for the length of the string.
Any ideas?
Something like this should work if you are using utf8 module from Lua 5.3 or luautf8, which works with LuaJIT:
local str = '这是一个中文字符串'
local tbl = {}
for p, c in utf8.codes(str) do
table.insert(tbl, utf8.char(c))
end
print(#tbl) -- prints 9
I haven't used non-english characters in lua before and my emulator just puts them in as '?' but something along the lines of this might work:
convert = function ( str )
local temp = {}
for c in str:gmatch('.') do
table.insert(temp, c)
end
return temp
end
This is a simple function that utilizes string.gmatch() to separate the string into individual characters and save them into a table. It would be used like this:
t = convert('abcd')
Which would make 't' a table containing a, b, c and d.
t[1] = a
t[2] = b
...
I am not sure if this will work for the Chinese characters but it is worth a shot.
So I've got a fairly deep hierarchy of record definitions:
-record(cat, {name = '_', attitude = '_',}).
-record(mat, {color = '_', fabric = '_'}).
-record(packet, {cat = '_', mat = '_'}).
-record(stamped_packet, {packet = '_', timestamp = '_'}).
-record(enchilada, {stamped_packet = '_', snarky_comment = ""}).
And now I've got an enchilada, and I want to make a new one that's
just like it except for the value of one of the subsubsubrecords.
Here's what I've been doing.
update_attitude(Ench0, NewState)
when is_record(Ench0, enchilada)->
%% Pick the old one apart.
#enchilada{stamped_packet = SP0} = Ench0,
#stamped_packet{packet = PK0} = SP0,
#packet{cat = Tag0} = PK0,
%% Build up the new one.
Tude1 = Tude0#cat{attitude = NewState},
PK1 = PK0#packet{cat = Tude1},
SP1 = SP0#stamped_packet{packet = PK1},
%% Thank God that's over.
Ench0#enchilada{stamped_packet = SP1}.
Just thinking about this is painful. Is there a better way?
As Hynek suggests, you can elide the temporary variables and do:
update_attitude(E = #enchilada{stamped_packet = (P = #packet{cat=C})},
NewAttitude) ->
E#enchilada{stamped_packet = P#packet{cat = C#cat{attitude=NewAttitude}}}.
Yariv Sadan got frustrated with the same issue and wrote Recless, a type inferring parse transform for records which would allow you to write:
-compile({parse_transform, recless}).
update_attitude(Enchilada = #enchilada{}, Attitude) ->
Enchilada.stamped_packet.packet.cat.attitude = Attitude.
Try this:
update_attitude(E = #enchilada{
stamped_packet = (SP = #stamped_packet{
packet = (P = #packet{
cat = C
})})}, NewState) ->
E#enchilada{
stamped_packet = SP#stamped_packet{
packet = P#packet{
cat = C#cat{
attitude = NewState
}}}}.
anyway, structures is not most powerful part of Erlang.