Regex -- Turku Agile Day 011

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Abstract Machine

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Glob

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Origin

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Functions

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Architecture

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Directed Graph (nondeterministic)

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Alphabet

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States

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Transition Table

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Nondeterministic Finite Automata (NFA)

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Directed Graph (DFA/NFA)

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Deterministic Finite Automata (DFA)

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Regular Expressions

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Matching One Character

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Operator #1: Concatenation

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Operator #2: Kleene Star

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Operator #3: Alternation

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Quiz #1

Keskiviikko|(Maanan|Tiis|Tors| Perjan|Lauan|Sunnun)tai

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Parentheses

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Quiz #2

saippuakivikauppias

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Finite

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Regular Regex?

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Greedy (Kleene Star)

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Backtracking (NFA)

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Leftmost (NFA Alternation)

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Dialects

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Regex Literal

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Architecture

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Regex Objects

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Match Object

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Quantifiers

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Quiz #3

(0|1|2)(0|1|2|3|4|5|6|7|8|9){2}

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Quantifier algebra

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Positive Closure over Closure

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Character Class

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Quiz #4

[a-z0-9._-]+@[a-z0-9.-]+\.[a-z]{2,6}

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Quiz #5

25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9]?[0-9]

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Metacharacters – shorthands

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Quiz #6

2(0|1)\d\d1

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Quiz #7

(0|(00|\+)358)(4\d|50)\d{7}

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Metacharacters – dot

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Economical use of Dot

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Quiz #8

.+@.+

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Metacharacters – Unicode

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Quiz #9

\d+(,\d\d)?\s?\u20AC

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Assertions – Anchor

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Quiz #10

^\s+

\s+$

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Assertions – Lookaround

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Quiz #11

^(?=.*\d)(?=.*([a-zA-Z])).{8,40}$

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Mode

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Capture and Backreference

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Quiz #12

<(\w+)[^>]*>[^<]*</\1>

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Lazy Quantifiers

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Web Test bench

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REPL Test bench

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Test-driven development

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Study data source

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Accept some incorrect

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Deny some correct

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Simple method

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Shrink or Expand

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Split

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Blend imperative and regex

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Context unaware

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Consider Regex modes

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Regex Inject Attack

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Documentation

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Use Lazy Quantifiers

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Fail fast

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Compile only once

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Minimize Nested Quantifiers

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Boundaries in find

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Applications

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Resources

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Staffan Nöteberg

Book:Pomodoro Technique Illustratedwww.pomodoro-book.com

Twitter: staffannoteberghttp://blog.staffannoteberg.com