EX1
We want to replace all vowels with @
str=""Where have all the flowers gone?"
str=RegexpReplace(str, "[aeiou]", "@")
---> "Wh@r@ h@v@ @ll th@ fl@w@rs g@n@?"
EX2
We want to change the format of a date
str="date: 14:27 28/03/2023"
str=RegexpReplace(str, "(\d{2})/(\d{2})/(\d{4})", "$2.$1.$3")
---> "date: 14:27 03.28.2023"
$0 is full match: "28/03/2023"
$1 is captured group number 1: "28"
$2 is captured group number 2: "03"
$3 is captured group number 3: "2023"
The "/" is not captured, is remplaced by "."
The regular expression language is a programming language with its vocabulary and grammar. Once integrated into AI2, users will gradually learn to master the concept, over several years if necessary.
[pcrepattern specification]
PCRE patterns may contain options, which are enclosed in (? ) sequences. Options can be grouped together: "(?imx)". Options following an hyphen are negated: "(?im-sx)".
Options appearing outside a group affect the remaining of the pattern from that point onwards. Options appearing inside a group affect that group only. Options loose their special meaning inside a character class, where they are treated literally.
(?i)
Caseless: matching becomes case-insensitive from that point on. By default, matching is case-sensitive.
regex="red|black" matche "the red king" but not "the Red king"
regex="(?i)red|black" matche "the red king" and "the Red king"
(?m)
Multiline: ^ and $ match at newline sequences within data. By default, multiline is off, ^ match at start of text and $ match at end of text.
regex="^A" does not match "Good\nAfternoon"
regex="(?m)^A" match "Good\nAfternoon"
(?s)
Single-line or DotAll: . matches anything including a newline sequence. By default, DotAll is off hence . does not match a newline sequence.
regex="oo.*?oo" does not match "Good\nAfternoon"
regex="(?s)oo.*?oo" match "Good\nAfternoon"
(?x)
eXtended: whitespaces outside character classes are ignored and # starts a comment up to the next solid newline in pattern. Meaningless whitespaces between components make regular expressions much more readable. By default, whitespaces match themselves and # is a literal character.
regex="oo .*? oo" does not match "Good Afternoon" because spaces in regex
regex="(?x)oo .*? oo #match" match "Good Afternoon"
He! Kevin ! New problem
I'm looking in a long text for words ending in "ing" to capitalize them.
I thought of:
Kevin.ReplaceAll("Parking: it's good, camping is better!", "\b\w*ing\b", upcase("$0"))
DON'T WORK!
Probably because of the call of the function upcase which puts the parameter on the stack and which erases the meaning of "$0".
In java there is:
replaceAll(Function, stringreplace)
Is it possible to translate in ai2?
// Java code to illustrate replaceAll() method with function
import java.util.regex.*;
public class regexp {
public static void main(String[] args)
{
// Get the regex to be checked
String regex =
"(?x) # Ignore WhiteSpace \n" +
"\\b # First or last char in a word \n" +
"\\w* # Alphanum, any number \n" +
"ing # Letters i n g \n" +
"\\b # First or last char in a word";
//String regex = "\\b\\w*ing\\b";
// Create a pattern from regex
Pattern pattern = Pattern.compile(regex);
// Get the String to be matched
String text = "Parking is good; camping, is better.";
// Create a matcher for the input String
Matcher matcher = pattern.matcher(text);
// Replace every matched pattern. toUpperCase() is example.
text = matcher.replaceAll(x -> x.group().toUpperCase());
System.out.println(text);
}
}
This code WORK in Java: "PARKING is good; CAMPING, is better."
