I would like to parse a big sentence, which can contain names in fsharp.
I posit that names is in the form first name + last name.
In the absence of a first name list (can't find, will do later), I say that a first name is a string of length 4 or more, same for the last name.
When I try my very smart parser
let firstorlastname x = (parray 4 letter) x
firstorlastname "JEAN"
firstorlastname "CHRISTOPHE"
So, it works for both, but the problem is that it consumes only 4 characters, which is not the desired behaviour for Christophe. I would like the whole word to be consumed.
How can I instruct FParsec to consume the entire word, but fail if the word is less than 4 characters ?
Haven't tested it, but I think this should do it:
let firstOrLastName = manyMinMaxSatisfy 4 Int32.MaxValue isLetter
Related
I have been trying to find all possible strings in between 2 strings
This is my input: "print/// to be able to put any amount of strings here endprint///"
The goal is to print every string in between print/// and endprint///
You can use Lua's string patterns to achieve that.
local text = "print/// to be able to put any amount of strings here endprint///"
print(text:match("print///(.*)endprint///"))
The pattern "print///(.*)endprint///" captures any character that is between "print///" and "endprint///"
Lua string patterns here
In this kind of problem, you don't use the greedy quantifiers * or +, instead, you use the lazy quantifier -. This is because * matches until the last occurrence of the sub-pattern after it, while - matches until the first occurence of the sub-pattern after it. So, you should use this pattern:
print///(.-)endprint///
And to match it in Lua, you do this:
local text = "print/// to be able to put any amount of strings here endprint///"
local match = text:match("print///(.-)endprint///")
-- `match` should now be the text in-between.
print(match) -- "to be able to put any amount of strings here "
I need to be able to print Hebrew characters on my Epson TM-T20ii. I am trying to get my printer to switch to character code page 36(PC862) using
ESC t36
for some reason the printer is switching to code page 3 and then printing the number 6.
Is there a way to let the printer know that the 6 is part of my command?
If you know of a different workaround please comment below.
Thanks
You are making a mistake, you aren't meant to replace n with an actual number.
The proper syntax in your case would be ←t$
Explanation: the manual says "ESC t n", n referring to the page sheet, however you don't replace n with a number rather with the ASCII character n, so in your example 36 = $ because $ is the 36th character on the ASCII table.
I'm attempting to construct a regex string in Swift 4 that gets characters at the start of a line where some are known and others aren't.
Let's say I've got a text file with line breaks for each word that reads as follows:
pucker
tuckered
duckerdinger
sucker punch
I'd like to get every word that contains "cker" in it that's 1 to 8 characters long.
I'm attempting to use this statement ^..cker..{1,8} as my RegEx string. All I'm getting is a partial match in Patterns (a Mac App), but Regex101.com's saying no match, and most importantly, Xcode says I'm using an invalid regex. I've also tried ^(..cker..) and a bazillion other variations.
What am I screwing up and how do I fix it? What I'm trying to do seems like it would be super simple, but I've wasted more time than I care to admit fiddling with it.
Update:
This has been the best I've been able to get so far...
"\\b..cker..", but I'm only able to get words that are exactly 8 characters long. I'd like to capture words that contain "cker" that are the 3rd, 4th, 5th, and 6th letters while capturing words up to 8 characters long.
Try this regex:
\b(?=.*cker)[a-zA-Z]{1,8}\b
Click for Demo
Explanation:
\b - matches a word boundary
(?=.*cker) - Positive Lookahead to make sure our string should contain the character sequence cker
[a-zA-Z]{1,8} - Matches 1 to 8 occurrences of a letter
\b - matches a word boundary
Currently I have code that looks like this:
somestring = "param=valueZ&456"
local stringToPrint = (somestring):gsub("(param=)[^&]+", "%1hello", 1)
StringToPrint will look like this:
param=hello&456
I have replaced all of the characters before the & with the string "hello". This is where my question becomes a little strange and specific.
I want my string to appear as: param=helloZ&456. In other words, I want to preserve the character right before the & when replacing the string valueZ with hello to make it helloZ instead. How can this be done?
I suggest:
somestring:gsub("param=[^&]*([^&])", "param=hello%1", 1)
See the Lua demo
Here, the pattern matches:
param= - literal substring param=
[^&]* - 0 or more chars other than & as many as possible
([^&]) - Group 1 capturing a symbol other than & (here, backtracking will occur, as the previous pattern grabs all such chars other than & and then the engine will take a step back and place the last char from that chunk into Group 1).
There are probably other ways to do this, but here is one:
somestring = "param=valueZ&456"
local stringToPrint = (somestring):gsub("(param=).-([^&]&)", "%1hello%2", 1)
print(stringToPrint)
The thing here is that I match the shortest string that ends with a character that is not & and a character that is &. Then I add the two ending characters to the replaced part.
I've been given a large file with a funny CSV format to parse into a database.
The separator character is a semicolon (;). If one of the fields contains a semicolon it is "escaped" by wrapping it in doublequotes, like this ";".
I have been assured that there will never be two adjacent fields with trailing/ leading doublequotes, so this format should technically be ok.
Now, for parsing it in VBScript I was thinking of
Replacing each instance of ";" with a GUID,
Splitting the line into an array by semicolon,
Running back through the array, replacing the GUIDs with ";"
It seems to be the quickest way. Is there a better way? I guess I could use substrings but this method seems to be acceptable...
Your method sounds fine with the caveat that there's absolutely no possibility that your GUID will occur in the text itself.
On approach I've used for this type of data before is to just split on the semi-colons regardless then, if two adjacent fields end and start with a quote, combine them.
For example:
Pax;is;a;good;guy";" so;says;his;wife.
becomes:
0 Pax
1 is
2 a
3 good
4 guy"
5 " so
6 says
7 his
8 wife.
Then, when you discover that fields 4 and 5 end and start (respectively) with a quote, you combine them by replacing the field 4 closing quote with a semicolon and removing the field 5 opening quote (and joining them of course).
0 Pax
1 is
2 a
3 good
4 guy; so
5 says
6 his
7 wife.
In pseudo-code, given:
input: A string, first character is input[0]; last
character is input[length]. Further, assume one dummy
character, input[length+1]. It can be anything except
; and ". This string is one line of the "CSV" file.
length: positive integer, number of characters in input
Do this:
set start = 0
if input[0] = ';':
you have a blank field in the beginning; do whatever with it
set start = 2
endif
for each c between 1 and length:
next iteration unless string[c] = ';'
if input[c-1] ≠ '"' or input[c+1] ≠ '"': // test for escape sequence ";"
found field consting of half-open range [start,c); do whatever
with it. Note that in the case of empty fields, start≥c, leaving
an empty range
set start = c+1
endif
end foreach
Untested, of course. Debugging code like this is always fun….
The special case of input[0] is to make sure we don't ever look at input[-1]. If you can make input[-1] safe, then you can get rid of that special case. You can also put a dummy character in input[0] and then start your data—and your parsing—from input[1].
One option would be to find instances of the regex:
[^"];[^"]
and then break the string apart with substring:
List<string> ret = new List<string>();
Regex r = new Regex(#"[^""];[^""]");
Match m;
while((m = r.Match(line)).Success)
{
ret.Add(line.Substring(0,m.Index + 1);
line = line.Substring(m.Index + 2);
}
(Sorry about the C#, I don't known VBScript)
Using quotes is normal for .csv files. If you have quotes in the field then you may see opening and closing and the embedded quote all strung together two or three in a row.
If you're using SQL Server you could try using T-SQL to handle everything for you.
SELECT * INTO MyTable FROM OPENDATASOURCE('Microsoft.JET.OLEDB.4.0',
'Data Source=F:\MyDirectory;Extended Properties="text;HDR=No"')...
[MyCsvFile#csv]
That will create and populate "MyTable". Read more on this subject here on SO.
I would recommend using RegEx to break up the strings.
Find every ';' that is not a part of
";" and change it to something else
that does not appear in your fields.
Then go through and replace ";" with ;
Now you have your fields with the correct data.
Most importers can swap out separator characters pretty easily.
This is basically your GUID idea. Just make sure the GUID is unique to your file before you start and you will be fine. I tend to start using 'Z'. After enough 'Z's, you will be unique (sometimes as few as 1-3 will do).
Jacob