# Underline With the flag `MD_FLAG_UNDERLINE`, MD4C sees underscore `_` rather as a mark denoting an underlined span rather than an ordinary emphasis (or a strong emphasis). ```````````````````````````````` example _foo_ .

foo

```````````````````````````````` In sequences of multiple underscores, each single one translates into an underline span mark. ```````````````````````````````` example ___foo___ .

foo

```````````````````````````````` Intra-word underscores are not recognized as underline marks: ```````````````````````````````` example foo_bar_baz .

foo_bar_baz

```````````````````````````````` Also the parser follows the standard understanding when the underscore can or cannot open or close a span. Therefore there is no underline in the following example because no underline can be seen as a closing mark. ```````````````````````````````` example _foo _bar .

_foo _bar

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