Check function parameters conform to a set of rules

If the parameters of a function are given in some combination but have an interdependency (e.g. different parametrisations of a probability distribution) or a constraint (like x>0) this function can simultaneously check all interrelations are satisfied and report on all the not conformant features of the parameters.

Usage

check_consistent(..., .env = rlang::caller_env())

Arguments

...

a set of rules to check either as x=y+z, or x>y. Single = assignment is checked for equality using identical otherwise the expressions are evaluated and checked they all are true. This for consistency with resolve_missing() which only uses assignment, and ignores logical expressions.

.env

the environment to check in

Value

nothing, throws an informative error if the checks fail.

Examples

testfn = function(pos, neg, n) {
  check_consistent(pos=n-neg, neg=n-pos, n=pos+neg, n>pos, n>neg)
}

testfn(pos = 1:4, neg=4:1, n=rep(5,4))
try(testfn(pos = 1:4, neg=5:2, n=rep(5,4)))
#> Error : inconsistent inputs detected:
#> 1) constraint 'pos = n - neg' is not met.
#> 2) constraint 'neg = n - pos' is not met.
#> 3) constraint 'n = pos + neg' is not met.
#> 4) constraint 'n > neg' is not met