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Included in:

- user-manual: Macro and Block Passthroughs
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The passthrough is the primary mechanism by which to escape content in AsciiDoc (far more comprehensive and consistent than using a backslash).
As the name implies, a passthrough passes content directly through to the output document without applying any <<user-manual#subs,substitutions>>.
When using the passthrough block or macro, it's possible to specify a custom set of substitutions to be applied before the content is reintroduced.
Other forms of passthroughs, such as the single and double plus, apply substitutions strictly for compliance with the output format.

WARNING: Using passthroughs to pass content (without substitutions) can couple your content to a specific output format, such as HTML.
In these cases, you should use conditional preprocessor directives to route passthrough content for different output formats based on the current backend.
