40 lines
1.1 KiB
Plaintext
40 lines
1.1 KiB
Plaintext
---
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title: "Printing a tibble: Tracking control flow"
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output: html_vignette
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vignette: >
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%\VignetteIndexEntry{Printing a tibble: Tracking control flow}
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%\VignetteEngine{knitr::rmarkdown}
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%\VignetteEncoding{UTF-8}
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---
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```{r, include = FALSE}
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knitr::opts_chunk$set(
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collapse = TRUE,
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comment = "#>"
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)
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```
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What happens when a tibble is printed?
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This vignette shows the actual control flow, powered by the [debugme package](https://github.com/r-lib/debugme#readme).
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See `vignette("printing")` for a detailed description of the control and data flows.
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To activate debugging, we need to set an environment variable before loading the pillar package.
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As a result, debug strings in pillar's code are replaced with calls to a logging function.
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By default, debugme also shows timestamps.
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This is disabled to keep the output stable.
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```{r eval = FALSE}
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Sys.setenv(DEBUGME = "!!!!pillar")
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Sys.setenv(DEBUGME_SHOW_TIMESTAMP = "no")
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library(pillar)
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tbl <- tibble::tibble(a = 1:3, b = tibble::tibble(c = 4:6, d = 7:9), e = 10:12)
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print(tbl, width = 23)
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```
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```{r echo = FALSE}
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writeLines(readLines("debugme.txt"))
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```
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