https://github.com/cynkra/struct

Strict modification of objects
https://github.com/cynkra/struct

Last synced: 16 days ago
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Strict modification of objects

• Host: GitHub
• URL: https://github.com/cynkra/struct
• Owner: cynkra
• License: other
• Created: 2024-02-19T11:38:11.000Z (10 months ago)
• Default Branch: main
• Last Pushed: 2024-03-13T10:48:02.000Z (9 months ago)
• Last Synced: 2024-11-02T16:08:16.066Z (about 1 month ago)
• Language: R
• Size: 24.4 KB
• Stars: 5
• Watchers: 2
• Forks: 1
• Open Issues: 2
• Metadata Files:
  • Readme: README.Rmd
  • License: LICENSE

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README

        
---

output: github_document

---

```{r, include = FALSE}

knitr::opts_chunk$set(

  collapse = TRUE,

  comment = "#>",

  fig.path = "man/figures/README-",

  out.width = "100%"

)

```

# struct

{struct} provides ways to modify objects more strictly, guaranteeing that we

keep the type of the modified element, where type is defined by `vctrs::vec_ptype()`.

The `struct()` function gives a subclass "struct" to the objects if its internal

type is list (thus including data frames), and recursively to its list components.

When assigning new values, we give it the "struct" subclass if relevant then 

use `vctrs::vec_cast()` to check the compatibility of the input with the output,

and apply coercion if necessary.

## Installation

Install with:

``` r

remotes::install_github("cynkra/struct")

```

## Example

```{r, error = TRUE}

library(struct)

library(tibble)

x1 <- list(

  a = 1,

  b = list(tibble(c = 3:4, d = 5:6)),

  c = tibble(e = 7:8, f = 9:10),

  y = list(z = c("a", "b"))

)

x2 <- deep_struct(x1)

x2

print_tree(x2)

# works

x2$a <- 11

x2$b <- list(tibble(c = 13:14, d = 15:16))

x2$c <- tibble(e = 17:18, f = 19:20)

# fails

x2$a <- c(11, 12)

x2$a <- "a"

x2$b <- list("a", "b")

x2$c <- 1

x2[["z"]]

```