Partial matching of strings with error checking

This function is the same as pmatch, but it can throw an error instead of NA if not match is found, and can be forced to throw the error if more than the desired number of matches is found.

Usage

pmatchSafe(
  x,
  table,
  useFirst = FALSE,
  error = TRUE,
  ignoreCase = TRUE,
  nmax = length(x),
  ...
)

Arguments

x: Character: String to match.
table: Character vector: Values to which to match.
useFirst: Logical: If TRUE, and there is more than one match for a given x, then the first value in table that matches x will be returned (without an error or warning).
error: Logical: If no match is found, return an error?
ignoreCase: Logical: If TRUE (default), ignore the case of values in x and table when checking for matches.
nmax: Positive numeric integer: Maximum allowable number of matches. If more than this number of matches is found, an error will be thrown (regardless of the value of error).
...: Arguments to pass to pmatch.

Value

One or more of the values in table.

Examples


pmatchSafe('ap', c('apples', 'oranges', 'bananas'))
#> [1] "apples"

pmatchSafe('AP', c('apples', 'oranges', 'bananas'))
#> [1] "apples"

pmatchSafe('AP', c('apples', 'oranges', 'bananas'),
    ignoreCase = FALSE, error = FALSE)
#> [1] NA

pmatchSafe(c('ba', 'ap'), c('apples', 'oranges', 'bananas'))
#> [1] "bananas" "apples" 

# No match:
tryCatch(
    pmatchSafe('kumquats', c('apples', 'oranges', 'bananas')),
  error = function(cond) FALSE
)
#> [1] FALSE

pmatchSafe('kumquats', c('apples', 'oranges', 'bananas'), error = FALSE)
#> [1] NA

pmatchSafe(c('ap', 'corn'), c('apples', 'oranges', 'bananas'), error = FALSE)
#> [1] "apples" NA      

# Too many matches:
tryCatch(
    pmatchSafe(c('ap', 'ba'), c('apples', 'oranges', 'bananas'), nmax = 1),
  error=function(cond) FALSE
)
#> [1] FALSE