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How are blank spaces represented in regular expressions?
Literal
Regular-expression [with-で] blank [topic-は] how-[as-のように] is-represented-[passive] [explanatory-polite-のでしょうか]?
A programming/technical question. 正規表現 ('regular expression') is a direct calque of the English term — 正規 ('regular, formal') + 表現 ('expression'). 空白 ('blank, white space') is the technical term for a space character in programming contexts. ~のでしょうか is a polite question softener, more formal than ~ですか. どのように 'in what way, how.' Typical of a technical forum post.