A "string" is a sequence of characters typically representing a unit of human-readable text. Questions on this topic deal with processing strings in programs, and how various languages and environments define and manipulate strings.

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2
votes
2answers
191 views

Do any languages other than Haskell implement strings as linked lists of characters?

Haskell’s String type is an alias for [Char] (i.e. a linked list of Chars). Does any other language use an implementation of strings like this?
-1
votes
1answer
125 views

Which file format should I use as an alternative to my current Excel worksheet? [closed]

My .NET application does its work and then creates a report (an Excel worksheet). That report contains thousands of short text strings [KEY - VALUE]. So Excel worksheets suites very well, one column ...
3
votes
1answer
640 views

Types of quotes for an HTML templating language

I'm developing a templating language, and now I'm trying to decide on what I should do with quotes. I'm thinking about having 3 different types of quotes which are all handled differently: ...
10
votes
2answers
6k views

Shortest Common Superstring: find shortest string that contains all given string fragments

Given some string fragments, I would like to find the shortest possible single string ("output string") that contains all the fragments. Fragments can overlap each other in the output string. Example:...
2
votes
1answer
49 views

finding optimal token definitions for compression

I have a collection of strings which have a lot of common substrings, and I'm trying to find a good way to define tokens to compress them. For instance, if my strings are: s1 = "String" s2 = "Bool" ...
0
votes
1answer
47 views

Most Pythonic way to remove first match of potential leading strings?

This is a bit difficult to describe, but I'll do my best. In Python, I can use string.startswith(tuple) to test for multiple matches. But startswith only returns a boolean answer, whether or not it ...
-1
votes
1answer
78 views

Parsing a string with multiple levels of key value pairs

I need to write a part of the program which will work with a string, find in it some substrings and copy they to dictionary. Example of the string: thestring ='\ #: somethings\nchars0 "substr0"\...
17
votes
6answers
12k views

Should a string constant be defined if it's only going to be used once?

We're implementing an adapter for Jaxen (an XPath library for Java) that allows us to use XPath to access the data model of our application. This is done by implementing classes which map strings (...
3
votes
2answers
170 views

Most efficient strategy for search large text areas for multiple values

I have a requirement for a service that does the following. Take a block of text and identify the server names in it (by name or ip address). So given: Lorem ipsum dolor sit amet, consectetur ...
5
votes
2answers
195 views

Is “use ”abc“.equals(myString) instead of myString.equals(”abc“) to avoid null pointer exception” already problematic in terms of business logic?

I heard numerous times that when comparing Strings in Java, to avoid null pointer exception, we should use "abc".equals(myString) instead of myString.equals("abc"), but my question is, is this idea ...
1
vote
1answer
44 views

Should arbitrary numbers be stored as strings in a database?

I'm using Google as a login system for my latest project. So, my users table has a column named googleid, which stores Google's unique user id, which is a number, with a few dozen digits. For example, ...
3
votes
1answer
173 views

Burrows-Wheeler transform backward search: how to find suffix index?

BWT backward search algorithm is pretty straightforward if we only need the multiplicity of a pattern. However I also need to find the suffix indices (i.e. positions in the reference string where a ...
25
votes
1answer
11k views

C++11 includes std::stoi, why not std::itos?

I noticed to my glee that C++11 has a std::sto@ family of functions for easily unpacking ints/floats/longs whatever from strings. I'm surprised however, that the opposite isn't implemented. Why didn't ...
7
votes
5answers
9k views

How do you compress ASCII strings into fewer bytes?

I'm working with an embedded device with a unique protocol that sends messages to other devices and I'm making an application that parses the sent packets. Each packet carries 8 bytes. The protocol is ...
-2
votes
1answer
107 views

Find missing number in sequence in string [closed]

I have a string that contains numbers in sequence. There are no delimiters between numbers. I have to find missing number in that sequence. For example: 176517661768 is missing the number: 1767 ...
7
votes
2answers
344 views

Compile-time checking for NULL initialized std::string

This is sort of the complementary question to How to best protect from 0 passed to std::string parameters?. Basically, I'm trying to figure out whether there is a way to have the compiler warn me if a ...
1
vote
4answers
691 views

Why do so many languages restrict string literals to a single source line? [closed]

In, for example, the Bash scripting language, the following creates a string called $VAR which begins at the first " quote and continues until the next unescaped " quote. $VAR=" hello world! ...
7
votes
4answers
2k views

Why do people put '\n' at the beginning of strings?

Very often I get into C code where printf format strings start with \n: printf( "\nHello" ); This in my opinion is an annoying thing that offers no advantages (rather many disadvantages!) with ...
2
votes
2answers
5k views

Assigning strings to pointer in C

My question is about pointers in C. As far as I've learned and searched, pointers can only store addresses of other variables, but cannot store the actual values (like integers or characters). But in ...
0
votes
1answer
131 views

Algorithm to get all possible forms of a word with varying suffixes [closed]

I'm writing an application in javascript where given a word, I need to get all the possible versions of the word with the suffix being the difference between each form. For example: "sponsor" should ...
2
votes
6answers
842 views

Find pattern in a string [closed]

How would one approach the following question: We have two strings: a normal alphanumeric string and a pattern string. the pattern string can be composed by alphanumeric chars plus the char "?" ...
-1
votes
1answer
241 views

In which cases and examples String in Java is not immutable? [duplicate]

If Strings are immutable in Java, why is the output of this code 2GB, instead of 1GB? class Laptop { String memory = "1GB"; } class Workshop { public static void main(String args[]) { ...
65
votes
11answers
25k views

Why is String immutable in Java?

I couldn't understand the reason of it. I always use String class like other developers, but when I modify the value of it, new instance of String created. What might be the reason of immutability ...
-1
votes
1answer
109 views

Speeding up appending text in C# [duplicate]

I'm trying to append text to a large amount of strings (in the thousands), and also do some other string manipulations. However, I have about 60 lines of if/else and string appending and it takes ...
0
votes
2answers
367 views

How to scramble a word, keeping first and last characters the same?

I have a task, which is to scramble a single word, whose size is greater than 3 letters. The scrambled word must not be equal to the original, and the first and last letters of the word must remain ...
4
votes
4answers
2k views

Why is %s better than + for concatenation?

I understand that we should use %s to concatenate a string rather than + in Python. I could do any of: hello = "hello" world = "world" print hello + " " + world print "%s %s" % (hello, world) print ...
0
votes
1answer
343 views

What is the purpose of chunking strings in natural language processing?

I see many examples of libraries that use a 'chunker' and also people asking how to write chunkers, but what is this for and why do we need it? Isn't it enough to split a text by whitespace or other ...
7
votes
6answers
1k views

Is “string literal” always the same as “hard-coded string”? [closed]

I am learning programming and often see the term "string literal" being used in various places. From the looks of it, it seems to be a synonym for "hard-coded string", but on another hand the term ...
-2
votes
2answers
97 views

Find index of string in an array of strings where overlap could occur

I am having some trouble writing a variant of sub-string search. Essentially the goal is to write a method that can perform sub-string search except that the source data is in an array of Strings ...
2
votes
3answers
346 views

Why do most language's definition of substring allow substring(“abc”, 3) => “”

I've seen most languages have it be the case for their substring method that using the length of a given string in the method as the start index will give you an empty string. It is most definitely ...
6
votes
7answers
23k views

string.format with variables vs inline variables

What are the pros/cons (if any) to using string output; int i = 10; output = string.Format("the int is {0}", i); versus string output; int i = 10; output = "the int is " + i; I have always ...
15
votes
3answers
16k views

Which string search algorithm is actually the fastest?

I have been stuck for some time on which is the fastest string search algorithm, heard many opinions, but in the end I'm not sure. I have heard some people saying that the fastest algorithm is Boyer-...
0
votes
2answers
147 views

Incrementing Strings in PHP (and Perl)

PHP allows you to increment strings. Why? Let's jump ahead a bit. Take the following code: $string = '9ZzZ'; echo ++$string; // 10AaA From a purist point of view this may seem like nonsense, ...
1
vote
0answers
77 views

Algorithm for evaluating line breaks efficiently [closed]

Consider following problem : Given: String input with the length n Font(-metrics) - potentially slow in usage Bounds of an abstract Textview which shall contain the text in a specific manner: e.g ...
9
votes
3answers
242 views

number of strings, when each character must occur even times

I've been bashing my skull at this problem for some time now, and its really starting to frustrate me. The problem is: I have a set of characters, A, B, C, and D. I have to tell in how many ways a ...
-2
votes
4answers
651 views

In C# Is using private constant strings better than using strings directly in the code? [closed]

Consider the following two cases: case 1: class A { private const string MyConst="Hello"; internal void CallMe() { System.Console.WriteLine(MyConst); } } Case2: class A { ...
0
votes
1answer
265 views

What operating systems will “\n” create a new line in? (Java) [closed]

(Java Version 8 Update 60) Hello. I am currently writing a program for my first Java assignment in college. My question is, in what operating systems will System.out.println("Hello,\n World"); ...
8
votes
6answers
1k views

What are the pros and cons of having a CaseInsensitiveString type in Java? [closed]

I'm tempted to create a final class CaseInsensitiveString implements CharSequence. This would allow us to define variables and fields of this type, instead of using a regular String. We can also have ...
1
vote
2answers
226 views

Why are Strings in StringPool considered insecure?

Passwords are recommended to be stored in char[] instead of String, as Strings are stored in StringPool. Read more here As per this question Strings in StringPool are not available directly. To ...
3
votes
1answer
67 views

CharSequence to represent a named object

I always followed the opinion to not abuse interfaces in case of decomposition. Usually I only implement them if I am absolutely sure to have a "is-a"-relation and avoid implementing them if there is ...
20
votes
3answers
2k views

Why are C string literals read-only?

What advantage(s) of string literals being read-only justify(-ies/-ied) the: Yet another way to shoot yourself in the foot char *foo = "bar"; foo[0] = 'd'; /* SEGFAULT */ Inability to elegantly ...
31
votes
6answers
141k views

Is initializing a char[] with a string literal bad practice?

I was reading a thread titled "strlen vs sizeof" on CodeGuru, and one of the replies states that "it's anyways [sic] bad practice to initialie [sic] a char array with a string literal." Is this true,...
1
vote
4answers
346 views

How can I avoid the use of strings?

I'm implementing a program where the user can 'create a musical scale' from a variety of notes (identified by their names), and the program will generate music from this scale. I want to implement a ...
4
votes
2answers
485 views

Why do people confuse C-type strings and STL strings [closed]

The last week I saw at least three questions where people were confused about the differences between char * and std::string or made some related mistakes. Don't get me wrong, I don't have a problem ...
4
votes
2answers
202 views

Are string characters assigned a numerical value in context of how they are assigned in a programming language?

For context I am fairly new to programming after returning back to it after programming a number of years ago... I was reading Bjarne's intro programming with C++ and was wondering if alphabetical ...
4
votes
2answers
195 views

why regex, when using global search and {0,} quantifier, match the end of the string?

I have asked a question here about js, regex, quantifiers and global search. I've understood finally how this works, but, let's take a concrete example and then I`ll write my question. Based on the ...
0
votes
0answers
80 views

clustering of strings with variable-length prefixes

I've got bunch of strings with variable-length prefixes (or postfixes - I can always revert them) as follows: 0155555555 523455555555 755555555 ... 87129999999999999 119999999999999 09119999999999999 ...
3
votes
3answers
3k views

Try to find a word in the dictionary that has most letters given

I recently came across an algorithm design problem that I'd like some help with: Given some letters, for example a,e,o,g,z,k,l,j,w,n and a dictionary of words. Find a word in the dictionary that ...
0
votes
2answers
353 views

Why can't I use an operator like plus sign to concatenate strings? [closed]

Why in Objective-C we should be typing explicit references to methods like stringByAppendingString to concatenate strings, when in some other languages we can use operators for that? For example, ...
0
votes
2answers
493 views

Why should I use lookup tables at all?

This question confirmed, what I was already aware of -- instead of directly storing strings in table, I should rather use integers or enums and join them with lookup table, to get, as a result, string,...