What does ?= do at the beginning ? since it checks if a pattern or character is followed by something like x(?=y) Why do we need it at the beginning?
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FCC Solution
/(?=\w{6})(?=\w*\d{2})/
Link
The lookahead starts at the current position. This link seems to provide a good explanation - Lookahead and Lookbehind Tutorial—Tips &Tricks
For the x(?=y) example, the current position is after the x and the lookahead checks for a y at that position.
For your (?=\w{6})(?=\w*\d{2}) example, you want it to look through the whole value, starting at the beginning.
Here’s a regex explainer/tester that shows both a flow-chart of what the regex does and lets you test values to see if they match - Online Regex tester and visualizer - Python, PHP, Ruby, JavaScript, Java
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The link you have attached provides a great explanation and it has a an advanced example of password validation. Thank you! not finding solution checkbox here
From what I understand now using the lookaheads at every group of the expression will not return a matched pattern but it only tests if true or false
Seems to have been removed.
Edit: It apparently only exists in some of the forum sections.
Indeed I have only seen it in the beginners -PHP category