carboncopy - An RStudio Add-In for inline reporting of datestamped output

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It is useful to present some of a program's output together with its code, even when we're working in plain .R scripts and not RMarkdown documents. We might want to do this for a few reasons, including:

1. We can show the code to other people and demonstrate what it does without having to reload large datasets or execute long-running processes.
2. If we do exploratory analyses to make decisions about data cleaning and processing, e.g. table() or fivenum() calls, we can keep the results of those analyses in the code as a paper trail.

This RStudio Add-In automates that by inserting the last expression's output as a comment, along with a datestamp showing when the code was last run for reportability and as a code smell.

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Instructions

Install it

You can install the development version of carboncopy like so:

# install.packages("remotes")
remotes::install_github("DesiQuintans/carboncopy")

(CRAN coming) (Addinslist coming)

Access it...

By binding to a keyboard shortcut

Bind carboncopy's Insert .Last.value as a comment function to a keyboard shortcut by going to Tools > Modify Keyboard Shortcuts and searching for last. I set it to Ctrl + \ so that I can run a block of code with Ctrl + Enter and then insert the result immediately with Ctrl + \.

From the Addins menu

From the Command Palette (by default, Ctrl + Shift + P)

Use it...

Note that the width of the output comment is based on the width of your Console Pane at the time you insert the comment. This is because the add-in tells R to print .Last.value to the current console, then captures that output and redirects it. Simply put, if your output is too wide or too narrow:

head(iris)
#   Sepal.Length Sepal.Width
# 1          5.1         3.5
# 2          4.9         3.0
# 3          4.7         3.2
# 4          4.6         3.1
# 5          5.0         3.6
# 6          5.4         3.9
#   Petal.Length Petal.Width
# 1          1.4         0.2
# 2          1.4         0.2
# 3          1.3         0.2
# 4          1.5         0.2
# 5          1.4         0.2
# 6          1.7         0.4
#   Species
# 1  setosa
# 2  setosa
# 3  setosa
# 4  setosa
# 5  setosa
# 6  setosa
#     < Last run: 2023-09-26 >

Then either zoom out in RStudio with [Ctrl] + [-] to make the text smaller, or change the width of your Console Pane, and then try again:

head(iris)
#   Sepal.Length Sepal.Width Petal.Length Petal.Width Species
# 1          5.1         3.5          1.4         0.2  setosa
# 2          4.9         3.0          1.4         0.2  setosa
# 3          4.7         3.2          1.3         0.2  setosa
# 4          4.6         3.1          1.5         0.2  setosa
# 5          5.0         3.6          1.4         0.2  setosa
# 6          5.4         3.9          1.7         0.4  setosa
#     < Last run: 2023-09-26 >

With functions that return something

Most R expressions return something that gets saved to .Last.value, so in most cases you can run a block of code and then invoke Insert .Last.value as a comment to insert the output in your document:

summary(beaver1$temp)
#  Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
# 36.33   36.76   36.87   36.86   36.96   37.53 
#     < Last run: 2023-09-26 >

With functions that return nothing except Console output

Some R expressions only print to the Console but return nothing. For example, stem() prints a text histogram to the Console but returns NULL, so this happens when you insert the last output:

stem(warpbreaks$breaks)
# NULL
#     < Last run: 2023-09-26 >

To capture the output of these, highlight the entire expression and then invoke Insert .Last.value as a comment. It will run your expression for you, capture the output directly, and insert it below.

stem(warpbreaks$breaks)
# The decimal point is 1 digit(s) to the right of the |
# 
# 1 | 0234555667788899
# 2 | 001111445666678889999
# 3 | 00156699
# 4 | 1234
# 5 | 124
# 6 | 7
# 7 | 0
# 
#     < Last run: 2023-09-26 >