// Simple regex literals
/pattern/
/hello world/
/\d+/
/[a-z]/

// Regex with flags
/pattern/gi
/test/img
/unicode/u
/dotall/s
/sticky/y

// Character classes
/[abc]/
/[^xyz]/
/[0-9]/
/[a-zA-Z]/
/[\w\s]/

// Quantifiers
/a*/
/b+/
/c?/
/d{3}/
/e{2,5}/
/f{4,}/

// Anchors
/^start/
/end$/
/\bword\b/
/\Bnot\B/

// Groups and alternation
/(group)/
/(?:non-capturing)/
/(?<named>group)/
/(a|b|c)/
/(?=lookahead)/
/(?!negative)/

// Escape sequences
/\./
/\\/
/\n/
/\t/
/\x41/
/\u0041/

// Complex patterns
/^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$/i
/https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}/
/(?:\d{3}|\(\d{3}\))([-\/\.])\d{3}\1\d{4}/

// Regex in context
const pattern = /test/g;
if (/^\d+$/.test(input)) {}
string.replace(/old/g, 'new');
text.match(/\w+/g);
data.split(/\s*,\s*/);

// Not regex (division operator context)
const result = 10 / 2;
const calc = a / b / c;
x = y /= 2;