grepict_rigid: helper for grepict
In renlund/dm: Data Management

this is essentially a helper function for grepict, see the documentation

grepict_rigid(
  pattern,
  x = NULL,
  data,
  ...,
  include = c(TRUE, TRUE),
  long = TRUE,
  verbose = TRUE,
  paste.alias = TRUE
)

`pattern`	a search string to pass to `grepl`
`x`	names of variables to search in (in order of importance, if applicable), if `NULL` all variables except 'id' and 'date' (which must exist) and 'begin' and 'end' (which might exist) are used as search variables
`data`	a data set that must contain 'id' and 'date', and optionally 'begin' and 'end'. If the latter are missing, the earliest and latest dates will be used, respectively.
`...`	arguments (beyond 'pattern' and 'x') passed to `grepl`
`include`	length 2 logical vector specifying if lower (first entry) and upper (second entry) bounds are inclusive (`TRUE`) or not (`FALSE`)
`long`	output format, if `TRUE` all hits have separate row, else the emphasis is on the first hit for each 'id' (by 'date' and 'x'). N.B `long = FALSE` will be slow for large datasets!
`verbose`	if `TRUE` the function will give helpful and/or annoying messages sometimes
`paste.alias`	if `long = FALSE` and if 'x' has a names attribute, this will be pasted onto some output variable names, unless you set override this behavour by setting this argument to zero