Regular Expressions 101

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/
>>(?<name>[A-Za-z]+)<<(?<price>\d+\.?\d+)!(?<quantity>\d+)
/
gm
>>
matches the characters >> literally (case sensitive)
Named Capture Group name
(?<name>[A-Za-z]+)
Match a single character present in the list below
[A-Za-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case sensitive)
a-z matches a single character in the range between a (index 97) and z (index 122) (case sensitive)
<<
matches the characters << literally (case sensitive)
Named Capture Group price
(?<price>\d+\.?\d+)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\.
matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
! matches the character ! with index 3310 (2116 or 418) literally (case sensitive)
Named Capture Group quantity
(?<quantity>\d+)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String