### 6.4.1 Markup construction in Scheme

The `markup` macro builds markup expressions in Scheme while providing a LilyPond-like syntax. For example,

```(markup #:column (#:line (#:bold #:italic "hello" #:raise 0.4 "world")
#:larger #:line ("foo" "bar" "baz")))
```

is equivalent to:

```\markup \column { \line { \bold \italic "hello" \raise #0.4 "world" }
\larger \line { foo bar baz } }
```

This example demonstrates the main translation rules between regular LilyPond markup syntax and Scheme markup syntax.

 LilyPond Scheme `\markup markup1` `(markup markup1)` `\markup { markup1 markup2 ... }` `(markup markup1 markup2 ... )` `\command` `#:command` `\variable` `variable` `\center-column { ... }` `#:center-column ( ... )` `string` `"string"` `#scheme-arg` `scheme-arg`

The whole Scheme language is accessible inside the `markup` macro. For example, You may use function calls inside `markup` in order to manipulate character strings. This is useful when defining new markup commands (see New markup command definition).

#### Known issues and warnings

The markup-list argument of commands such as `#:line`, `#:center`, and `#:column` cannot be a variable or the result of a function call.

 ```(markup #:line (function-that-returns-markups)) ```

is invalid. One should use the `make-line-markup`, `make-center-markup`, or `make-column-markup` functions instead,

 ```(markup (make-line-markup (function-that-returns-markups))) ```

Other languages: español.