Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Generated Code

import Foundation let pattern = ##"[\#(/)_\-\=\!\:]"## let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = ##""" #/usr/bin/python3 from bisect import bisect_right def binary_search(vector,x): i = bisect_right(vector,x) if i != len(vector)+1 and vector[i-1] == x: return i-1 return -1 def is_prime(vector,number): return 1 if binary_search(vector,number) != -1 else 0 def prime_vector(num): ret = [] for a in range(2,num+1): if a == 2 or a == 3 or a == 5 or a == 7 or a == 11: ret.append(a) elif a %2 == 0 or a%3 == 0 or a%5 == 0 or a%7==0 or a%11 == 0: continue else: ret.append(a) return ret number = int(input()) prime = prime_vector(number) ret = [] p = 0 while number: if is_prime(prime,number): ret.append(number) break elif number%prime[p] == 0: ret.append(prime[p]) number = int(number / prime[p]) else: p = p + 1 for a in range((len(ret))): print(ret[a],end=" ") """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(result)

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression