Replace every other character if it's a \d with * (only those in even positions: 2, 4, 6, etc). Example: a1b2cde3g45hi6 should become abcdeg4hi6

Use substitution to put commas in all numbers to separate the thousands. ie: 12345678 → 12,345,678. The number could be in a sentence, and there may be more than one number in the sentence.

Validate a line in quotes. Return one (and only one) backreference with the text. ie: quoted text from "quoted text". Note: a \ escapes any char, so \" is a valid escape.

In an HTML page, replace the text micro with µ. Oh, and don't screw up the code: don't replace inside or &entities;

Purpose: This is supposed to be a learning process. The first 1-9 tasks are supposed to be done with using "standard" regex, ie, teach the user to use \s, \w, \d, aswell as backrefs and similar basic things. Later down the road, at task 10-13 we start introducing them to lookarounds. These are fairl...

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Validación para fechas en formato ISO 8601 como 2024-12-13

Validación de fecha de formato europeo 13/12/2024

ABCD12 o AB1234

1900 2024

test@g.cn

912345678 ó +56912345678 ó 56912345678

ABC123DEF12A

15.000.000-9

15000000-9

Antonio-Marcos O'Higgins González

This is made to validate an ISO 8601 input in a Terraform variable validation block: validation { condition = can(regex("^P(\\d+Y)?(\\d+M)?(\\d+D)?(T(\\d+H)?(\\d+M)?(\\d+S)?)?$", var.value)) error_message = "The value must be a valid ISO 8601 duration string representing time. (e.g. PT...

Tested in 2024 with various share/embed methods on YouTube video page

Allowing all firsnames written with Latin text like Björn or D'Mariüsz

for correctly parsing numbers in SVG attributes like path d or viewBox with regex v2: added support for scientific notation