27.10 Alignment

20200105

Align the assignment operator for blocks of assignments. It is easier for us to read the assignments in a tabular form than it is when it is jagged. This is akin to reading data in tables—such data is much easier to read when it is aligned. Space is used to enhance readability.

Preferred

a       <- 42
another <- 666
b       <- mean(x)
brother <- sum(x)/length(x)

Default

a <- 42
another <- 666
b <- mean(x)
brother <- sum(x)/length(x)

We might choose to align %>% in pipelines and base::+ for layers for a visual symmetry to avoid the operators being lost amongst the text. This requires extra work and is not supported by editors and there is a risk the operator too far to the right is overlooked on an inspection of the code.

Preferred

ds        <- weatherAUS
names(ds) <- rattle::normVarNames(names(ds))
ds %>%
  group_by(location) %>%
  mutate(rainfall=cumsum(risk_mm)) %>%
  ggplot(aes(date, rainfall)) +
  geom_line() +
  facet_wrap(~location) +
  theme(axis.text.x=element_text(angle=90))

Alternative

ds        <- weatherAUS
names(ds) <- rattle::normVarNames(names(ds))
ds                                         %>%
  group_by(location)                       %>%
  mutate(rainfall=cumsum(risk_mm))         %>%
  ggplot(aes(date, rainfall))               +
  geom_line()                               +
  facet_wrap(~location)                     +
  theme(axis.text.x=element_text(angle=90))

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