---
title: "Codebraid with Julia"
---


## Inline code


### Run

Inline code with `.cb-run` gives raw stdout.

`println(1 + 2)`{.julia .cb-run example=true}


### Expression and inline notebook

Inline code with `.cb-expr` evaluates an expression and then inserts the raw
output into the document, where it is interpreted as Markdown.  Inline code
with `.cb-nb` (`nb` is short for `notebook`) is similar, except output is
shown verbatim.

`"\$\\sin(30^\\circ) = $(sind(30))\$"`{.julia .cb-expr example=true}

`"\$e^{\\pi/4} = $(exp(pi/4))\$"`{.julia .cb-expr example=true}

`"\$e^{\\pi/4} = $(exp(pi/4))\$"`{.julia .cb-nb example=true}



### Stderr

In the event of an error, inline code automatically shows stderr by default.
This code is executed in its own session, `inline_error`, so that it does
not impact other examples.

`1 + "a"`{.julia .cb-run session=inline_error example=true}


### Source errors

A message is also displayed for errors in the Markdown source.  This usually
includes the name of the document source and the approximate line number.

`println(1 + 2)`{.jlia .cb-run session=inline_source_error example=true}



## Block code


### Run

Code blocks with `.cb-run` give raw stdout.  There is continuity between code
blocks so long as they are in the same session; variables persist.


```{.julia .cb-run session=hello example=true}
x = "Hello from *Julia!*"
```

```{.julia .cb-run session=hello example=true}
println(x)
```



### Notebook

Code blocks with `.cb-nb` show the code and also the verbatim stdout.

```{.julia .cb-nb session=random example=true}
using Random
using Statistics
Random.seed!(1)
rnums = rand(1:100, 10)
println("Random numbers: $(rnums)")
println("Median: $(median(rnums))")
println("Mean: $(mean(rnums))")
```


### Stderr

Code blocks automatically show stderr by default.

```{.julia .cb-nb .line_numbers session=block_error example=true}
var = 123
println(var)
flush(stdout)
var += "a"
```


### Source errors

A message is also displayed for errors in the Markdown source.  This usually
includes the name of the document source and the approximate line number.

```{.julia .cb-ruuun session=block_source_error example=true}
println(1 + 2)
```


## Other options

By default, stdout and stderr are only shown if they are non-empty.  In some
situations, it may be useful to represent empty output visually as
confirmation that there indeed was none.

```{.julia .cb-run show=code+stdout+stderr:verbatim_or_empty example=true}
x = 1 + 2
```


It is also possible to selectively hide output from a code chunk.

```{.julia .cb-nb hide=stdout example=true}
println(x)
```

`hide` takes any combination of `code`, `stderr`, and `stdout`, or simply
`all`.