11.1.2 Inserting ‘{ ‘}’ with @{ @} and @l rbracechar{}

@{ produces a single ‘{’ in the output, and @} produces a single ‘}’. Do not put braces after either an @{ or an @} command.

@lbracechar{} and @rbracechar{} also produce single ‘{’ and ‘}’ characters in the output. They do need following braces, as usual for alphabetic commands. In inline conditionals (see Inline Conditionals: @inline, @inlineifelse, @inlineraw), it can be necessary to avoid using literal brace characters in the source (and may be clearer in other contexts).