const regex = /([1-9][0-9]*[eE][1-9][0-9]*|(([1-9][0-9]*\.)|(\.[0-9]+))([0-9]*)?([eE][\-\+]?[1-9][0-9]*)?)/mg;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('([1-9][0-9]*[eE][1-9][0-9]*|(([1-9][0-9]*\\.)|(\\.[0-9]+))([0-9]*)?([eE][\\-\\+]?[1-9][0-9]*)?)', 'mg')
const str = `Matches
3.
3.3
3.3e2
3.3e-1
.1e1
1.11e12
1.3e-1
.1e1
.2e-14
5E6
No match
3
E9
.e3
7E
# Saker
Exponent:
[eE][\\-\\+]?[1-9][0-9]*
Siffra:
[1-9][0-9]*
# Förklaring
Stora parantesen
Alt1:
Siffra sen E utan punkt (slutar)
[1-9][0-9]*[eE][1-9][0-9]*
Alt2:
(([1-9][0-9]*\\.)|(\\.[0-9]+))([0-9]*)?([eE][\\-\\+]?[1-9][0-9]*)?
vänsta sidan innan ([0-9]*)?
parantes (([1-9][0-9]*\\.)|(\\.[0-9]+))
Alt1: ([1-9][0-9]*\\.)
Non Zero leading- siffra sen punkt
Alt2: (\\.[0-9]+)
Punkt sen (måste) siffra
Högra sidan ([0-9]*)?([eE][\\-\\+]?[1-9][0-9]*)?
([0-9]*)?
kanske siffra
([eE][\\-\\+]?[1-9][0-9]*)?
kanske exponent
`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions