const regex = /<!ELEMENT\s+
((?'elname'\S+)\s+)
((?'rank'\d+)\s+)?
(?'tagOmit'
(?'start'[-oO])\s+
(?'end'[-oO])\s+
)?
(?'content'
(?'keyword'(ANY|EMPTY|CDATA|RDATA))|
(?'contentGrp' \(.*\)[*+?]?)
)
(?'exceptions'
(\s+\-(?'exclusion'\(.+\)))?
(\s+\+(?'inclusion'\(.+\)))?
)
\s*>/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('<!ELEMENT\\s+
((?\'elname\'\\S+)\\s+)
((?\'rank\'\\d+)\\s+)?
(?\'tagOmit\'
(?\'start\'[-oO])\\s+
(?\'end\'[-oO])\\s+
)?
(?\'content\'
(?\'keyword\'(ANY|EMPTY|CDATA|RDATA))|
(?\'contentGrp\' \\(.*\\)[*+?]?)
)
(?\'exceptions\'
(\\s+\\-(?\'exclusion\'\\(.+\\)))?
(\\s+\\+(?\'inclusion\'\\(.+\\)))?
)
\\s*>', 'gm')
const str = `<!ELEMENT FTNOTE - - ((PARA | PARA-EFF-GROUP | PARA-EFF-CHOICE | TABLE | UN-LIST | NOTE | TABLE-EFF-GROUP | TABLE-EFF-CHOICE)+)
-(FTNOTE | NOTE | TABLE | GROUND-TEST | CORRECTIVE-ACTION)>
<!ELEMENT ENTRY - - (WARNING | CAUTION | NOTE | (PARA | UN-LIST | PARA-EFF-GROUP | PARA-EFF-CHOICE)*)
-(ENTRY | GRAPHIC-COLLECTION)
+(INFOMARK | FTNOTE-REF)>
<!ELEMENT COLSPEC - o EMPTY>
<!ELEMENT TGROUP - - (COLSPEC+, THEAD?, TBODY)>
<!ELEMENT TABLE - - (TITLE?, TGROUP, FTNOTE*)
-(TABLE | TABLE-NO-TITLE | GROUND-TEST | CORRECTIVE-ACTION)
+(INFOMARK | INCLUDED-SUBDOC | INCLUDED-SOURCE-DATA | EFF-NONE)>`;
// 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