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Produces a consistently formatted error message and stops execution. Intended for use inside custom validation steps created with require_custom(), so they produce the same structured errors as built-in steps.

Usage

fail(path, message, found = NULL, at = NULL)

Arguments

path

the full path (e.g. "x" or "newdata$x2").

message

the specific failure message.

found

optional value to show on a Found: line.

at

optional integer positions to show on an At: line.

Details

Format: path: message, with optional Found: and At: lines.

Examples

if (FALSE) { # \dontrun{
fail("x", "must be positive", found = -3, at = 2L)
# Error: x: must be positive
#   Found: -3
#   At: 2
} # }