im trying to make locals with Chinese letters
local 屁 = p
or
屁 = p
none of those work
any ways to do it?
You can't do this as "屁" is not a valid Lua identifier.
Lua identifiers can only have letters, numbers and underscores and must not start with a number.
However, you can create a table with a key 屁:
local chinese_letters = {
["屁"] = p
}
And access it as chinese_letters["屁"], for example
local chinese_letters = {
["屁"] = 10
}
print(chinese_letters["屁"])
By the way, the correct name for these chinese characters is Hanzi
Related
I have stumbled upon this line of code and I am not sure what the [ ? ] part represents (my guess is it's a sort of a wildcard but I searched it for a while and couldn't find anything):
['?'] = function() return is_canadian and "eh" or "" end
I understand that RHS is a functional ternary operator. I am curious about the LHS and what it actually is.
Edit: reference (2nd example):
http://lua-users.org/wiki/SwitchStatement
Actually, it is quite simple.
local t = {
a = "aah",
b = "bee",
c = "see",
It maps each letter to a sound pronunciation. Here, a need to be pronounced aah and b need to be pronounced bee and so on. Some letters have a different pronunciation if in american english or canadian english. So not every letter can be mapped to a single sound.
z = function() return is_canadian and "zed" or "zee" end,
['?'] = function() return is_canadian and "eh" or "" end
In the mapping, the letter z and the letter ? have a different prononciation in american english or canadian english. When the program will try to get the prononciation of '?', it will calls a function to check whether the user want to use canadian english or another english and the function will returns either zed or zee.
Finally, the 2 following notations have the same meaning:
local t1 = {
a = "aah",
b = "bee",
["?"] = "bee"
}
local t2 = {
["a"] = "aah",
["b"] = "bee",
["?"] = "bee"
}
If you look closely at the code linked in the question, you'll see that this line is part of a table constructor (the part inside {}). It is not a full statement on its own. As mentioned in the comments, it would be a syntax error outside of a table constructor. ['?'] is simply a string key.
The other posts alreay explained what that code does, so let me explain why it needs to be written that way.
['?'] = function() return is_canadian and "eh" or "" end is embedded in {}
It is part of a table constructor and assigns a function value to the string key '?'
local tbl = {a = 1} is syntactic sugar for local tbl = {['a'] = 1} or
local tbl = {}
tbl['a'] = 1
String keys that allow that convenient syntax must follow Lua's lexical conventions and hence may only contain letters, digits and underscore. They must not start with a digit.
So local a = {? = 1} is not possible. It will cause a syntax error unexpected symbol near '?' Therefor you have to explicitly provide a string value in square brackets as in local a = {['?'] = 1}
they gave each table element its own line
local a = {
1,
2,
3
}
This greatly improves readability for long table elements or very long tables and allows you maintain a maximum line length.
You'll agree that
local tbl = {
z = function() return is_canadian and "zed" or "zee" end,
['?'] = function() return is_canadian and "eh" or "" end
}
looks a lot cleaner than
local tbl = {z = function() return is_canadian and "zed" or "zee" end,['?'] = function() return is_canadian and "eh" or "" end}
as a followup question to lua tables - allowed values and syntax:
I need a table that equates large numbers to strings. The catch seems to be that strings with punctuation are not allowed:
local Names = {
[7022003001] = fulsom jct, OH
[7022003002] = kennedy center, NY
}
but neither are quotes:
local Names = {
[7022003001] = "fulsom jct, OH"
[7022003002] = "kennedy center, NY"
}
I have even tried without any spaces:
local Names = {
[7022003001] = fulsomjctOH
[7022003002] = kennedycenterNY
}
When this module is loaded, wireshark complains "}" is expected to close "{" at line . How can I implement a table with a string that contains spaces and punctuation?
As per Lua Reference Manual - 3.1 - Lexical Conventions:
A short literal string can be delimited by matching single or double quotes, and can contain the (...) C-like escape sequences (...).
That means the short literal string in Lua is:
local foo = "I'm a string literal"
This matches your second example. The reason why it fails is because it lacks a separator between table members:
local Names = {
[7022003001] = "fulsom jct, OH",
[7022003002] = "kennedy center, NY"
}
You can also add a trailing separator after the last member.
The more detailed description of the table constructor can be found in 3.4.9 - Table Constructors. It could be summed up by the example provided there:
a = { [f(1)] = g; "x", "y"; x = 1, f(x), [30] = 23; 45 }
I really, really recommend using the Lua Reference Manual, it is an amazing helper.
I also highly encourage you to read some basic tutorials e.g. Learn Lua in 15 minutes. They should give you an overview of the language you are trying to use.
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.
How can I convert a string like s = "6.1101,17.592,3.3245\n" to numbers in Lua.
In python, I usually do
a = s.strip().split(',')
a = [float(i) for i in a]
What is the proper way to do this with Lua?
This is fairly trivial; just do a repeated match:
for match in s:gmatch("([%d%.%+%-]+),?") do
output[#output + 1] = tonumber(match)
end
This of course assumes that there are no spaces in the numbers.
I must replace all of these characters, "①②③④⑤⑥⑦⑧⑨⑩", with "\item".
I have used this code:
stra = string.gsub(text, "①", "\\item")
strb = string.gsub(stra, "②", "\\item")
strc = string.gsub(strb, "③", "\\item")
strd = string.gsub(strc, "④", "\\item")
stre = string.gsub(strd, "⑤", "\\item")
However, this is very verbose. Is there a simpler way to replace all of those items?
local symbols_trans = {
["\226\145\160"]--[[①]] = "\\item1",
["\226\145\161"]--[[②]] = "\\bananas",
["\226\145\162"]--[[③]] = "\\cactus",
["\226\145\163"]--[[④]] = "\\etc",
["\226\145\164"]--[[⑤]] = "\\item5",
["\226\145\165"]--[[⑥]] = "\\item6",
["\226\145\166"]--[[⑦]] = "\\item7",
["\226\145\167"]--[[⑧]] = "\\item8",
["\226\145\168"]--[[⑨]] = "\\item9",
["\226\145\169"]--[[⑩]] = "\\item10",
}
text = string.gsub(text, "(\266\145.)", symbol_trans)
Or if you want to replace them all with"\\item":
text = string.gsub(text,
"\266\145[\160-\169]",
"\\item"
)
[\160-\169] is equivalent to [\160\161\162\163\164\165\166\167\168\169].
See the Lua manual for information on ranges and, in general, Lua patterns.
You could also be fancy:
text = string.gsub(text,
"\266\145([\160-169])",
function(c)
return "\\item"..(string.byte(c)-160+1)
end
)
This will turn ① into \item1, ② into \item2, and so on.
Use a "set" as described in the tutorial: http://lua-users.org/wiki/PatternsTutorial
string.gsub(text, "[①②③④⑤⑥⑦⑧⑨⑩]", "\\item")
Is there a simpler way to replace all of those items?
Not without a Lua pattern matching library that knows what UTF-8 is. Lua is not Unicode aware; it has no idea how to search for Unicode symbols.
If you're using some non-multibyte encoding, then what John suggested might work. But not if it's UTF-8.
For your specific case, you could always do this:
local symbolsToChange { "①", "②", ...}
for i, sym in ipairs(symbolsToChange) do
string.gsub(text, sym, "\\item")
end