README.Rmd

---
output: github_document
---

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```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  fig.path = "man/figures/README-",
  out.width = "100%"
)
```

# flow <img src='man/figures/logo.png' align="right" height="139" />

*{flow}* provides tools to visualize as flow diagrams the logic of functions, 
expressions or scripts and ease debugging.

Use cases are : 

* Deciphering other people's code
* Getting more comfortable with our own code by easing a visual understanding of its structure
* Documentation
* Debugging
* Inspect unit test results
* Providing a higher level view of an algorithm to collaborators
* Education

## Installation

Install from CRAN with:

``` r
install.packages("flow")
```

Or install development version from github:

``` r
remotes::install_github("moodymudskipper/flow")
```
## Example

```{r, eval=TRUE}
library(flow)
```

Using default nomnoml engine

```{r, eval=FALSE}
flow_view(rle)
```

![nomnoml](man/figures/README_nomnoml.png)

Using plantuml engine (make sure the [{plantuml}](https://github.com/rkrug/plantuml) package is installed).

```{r, eval=FALSE}
flow_view(rle, engine = "plantuml")
```

![plantuml](man/figures/README_plantuml.png)

## Additional functions

* `flow_run()` to display not only the diagram, but the logical path taken by a specific call
* `flow_compare_runs()` display the logical path of 2 calls to see where they diverge
* `flow_debug()`/`flow_undebug()` to use basically use `flow_run()` on a function wherever it's called
* `flow_view_vars()` to display the dependencies between variables in a function
* `flow_view_deps()` to display recursively all the functions that your function calls
* `flow_view_uses()` to display recursively all the functions that call your function
* `flow_view_shiny()` to display the modular structure of your shiny app
* `flow_view_source_calls()` to display dependency tree of scripts sourcing each other
* `flow_doc()` to build a package's documentation using flow diagrams
* `flow_test()` to show what happens in your unit tests
* `flow_embed()` to embed diagrams in your documentation.

See more in vignettes.

## Notes

Make sure to check the vignettes for a detailed breakdown of all features.


*{flow}* is built on top of Javier Luraschi's *{nomnoml}* package, and 
Rainer M Krug 's *{plantuml}* package, the latter only available from 
[github](https://github.com/rkrug/plantuml)
at the moment.