source: node_modules/prismjs/components/prism-fortran.js

Prism.languages.fortran = {
        'quoted-number': {
                pattern: /[BOZ](['"])[A-F0-9]+\1/i,
                alias: 'number'
        },
        'string': {
                pattern: /(?:\b\w+_)?(['"])(?:\1\1|&(?:\r\n?|\n)(?:[ \t]*!.*(?:\r\n?|\n)|(?![ \t]*!))|(?!\1).)*(?:\1|&)/,
                inside: {
                        'comment': {
                                pattern: /(&(?:\r\n?|\n)\s*)!.*/,
                                lookbehind: true
                        }
                }
        },
        'comment': {
                pattern: /!.*/,
                greedy: true
        },
        'boolean': /\.(?:FALSE|TRUE)\.(?:_\w+)?/i,
        'number': /(?:\b\d+(?:\.\d*)?|\B\.\d+)(?:[ED][+-]?\d+)?(?:_\w+)?/i,
        'keyword': [
                // Types
                /\b(?:CHARACTER|COMPLEX|DOUBLE ?PRECISION|INTEGER|LOGICAL|REAL)\b/i,
                // END statements
                /\b(?:END ?)?(?:BLOCK ?DATA|DO|FILE|FORALL|FUNCTION|IF|INTERFACE|MODULE(?! PROCEDURE)|PROGRAM|SELECT|SUBROUTINE|TYPE|WHERE)\b/i,
                // Statements
                /\b(?:ALLOCATABLE|ALLOCATE|BACKSPACE|CALL|CASE|CLOSE|COMMON|CONTAINS|CONTINUE|CYCLE|DATA|DEALLOCATE|DIMENSION|DO|END|EQUIVALENCE|EXIT|EXTERNAL|FORMAT|GO ?TO|IMPLICIT(?: NONE)?|INQUIRE|INTENT|INTRINSIC|MODULE PROCEDURE|NAMELIST|NULLIFY|OPEN|OPTIONAL|PARAMETER|POINTER|PRINT|PRIVATE|PUBLIC|READ|RETURN|REWIND|SAVE|SELECT|STOP|TARGET|WHILE|WRITE)\b/i,
                // Others
                /\b(?:ASSIGNMENT|DEFAULT|ELEMENTAL|ELSE|ELSEIF|ELSEWHERE|ENTRY|IN|INCLUDE|INOUT|KIND|NULL|ONLY|OPERATOR|OUT|PURE|RECURSIVE|RESULT|SEQUENCE|STAT|THEN|USE)\b/i
        ],
        'operator': [
                /\*\*|\/\/|=>|[=\/]=|[<>]=?|::|[+\-*=%]|\.[A-Z]+\./i,
                {
                        // Use lookbehind to prevent confusion with (/ /)
                        pattern: /(^|(?!\().)\/(?!\))/,
                        lookbehind: true
                }
        ],
        'punctuation': /\(\/|\/\)|[(),;:&]/
};