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mermaid

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Markdown-ish syntax for generating flowcharts, mindmaps, sequence diagrams, class diagrams, gantt charts, git graphs and more.

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export declare const frontMatterRegex: RegExp; export declare const directiveRegex: RegExp; export declare const anyCommentRegex: RegExp; /** * Strip `%%` comment runs exactly like `text.replace(anyCommentRegex, '\n')`, in linear time. * * A scanner rather than a regex, because no variant of this pattern is linear. Every regex form * carries a `\s*` that can cross newlines, and `/m` gives the engine a candidate start at each * line, so an all-whitespace document has the match attempt rescan the remaining run once per * line. Two shapes are quadratic in the released pattern and in the guarded `(^|\S)\s*%%.*\n` * that replaced it, both inside the default 50k `maxTextSize`: * * ``` * ('\n' + ' '.repeat(4)).repeat(10_000) all whitespace, many lines 256ms * '%%' + 'x%%'.repeat(16_000) no terminating newline 339ms * ``` * * against 0.1ms for ordinary diagram text of the same size. The guard cut the constant roughly * 40x but left the exponent alone, which is what CodeQL and the CWE-1333 review both caught. * * The scan walks forward once. For each `%%` it takes the line's terminating newline as the end * of the match — `.` never matches a newline, so the regex ends at that same character — and * extends left over the preceding whitespace run, never past the previous match. Each character * is visited at most twice, so the work is linear in the input and independent of how the * whitespace is arranged. * * A `%%` with no newline after it is left alone, because `%%.*\n` cannot match without one. */ export declare const stripAnyComments: (text: string) => string;