checkValue: Check functions for values
In jefferys/DataRepo: Manage a large data file repository
Description
Usage
Arguments
Details
Value
Functions
Examples
Description
A check function test something about its first (required) parameter and
returns either an empty string if the check succeeds or a non-empty string if
the check fails. Even when a test fails due to an error, the error is caught
and a message will be returned. The check functions described here test
various properties of values.
Usage
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checkIsNull(value)
checkIsNotNull(value)
checkLength(value, minimumLength = 0, maximumLength = Inf)
checkIsTrue(value)
checkIsFalse(value)
Arguments
value
A value to check.
minimumLength
The minimum length value must have. Shorter than
this and the check will fail. The default is 0. Often abbreviated 'min'.
maximumLength
The maximum length value must have. Longer than this
and the check will fail. The default is Inf. Often abbreviated 'max'.
Details
Many of the these functions are simple wrappers around existing R functions.
Note, calling any of these functions with an unused parameters will cause an
actual error as that is thrown before the called function begins executing
and hence can not be trapped and converted to a message by the called
function.
Value
All functions return either an empty string if the check succeeds or
a non-empty string if the check fails (including if checking causes an
error.)
Functions
-
checkIsNull: Use to test if a value is NULL. Returns one
of:
"" (empty string)
Check succeeded as value was NULL.
"Is not null."
Check failed as value was something other than NULL.
"Checking for null failed with the following error: ..."
Check failed unexpectedly with an error.
-
checkIsNotNull: Use to test that a value is not NULL. Returns
one of:
"" (empty string)
Check succeeded as value was something other than NULL.
"Is null."
Check failed as value was NULL.
"Checking for null failed with the following error: ..."
Check failed unexpectedly with an error.
-
checkLength: Use to test that a value has a length between
minimumLength and maximumLength, inclusive. By default checks
that length is between 0 and Inf, so you need to supply at
least one of these two extra parameters to do anything useful. Returns one
of:
"" (empty string)
Check succeeded as value had a length >= min and had a length <=
max.
"Length is not between min and max."
Check failed as value had a length > max, or had a length < min
(or both min and max were chosen poorly!).
"Length is not length."
Check failed as value did not have the specified length. This
message is only given when max == min.
"Bad parameter 'value'. ..."
Check failed due to an invalid value parameter. This probably
means that the provided value was NULL.
checkLength(NULL) results in a failure string, contrary to R's
very tolerant evaluation of length(NULL) as 0.
"Checking for length failed with the following error: ..."
Check failed unexpectedly with an error.
-
checkIsTrue: Use to check if an expression (value)
evaluates to TRUE. Returns one of:
"" (empty string)
Check succeeded as value evaluated to logical TRUE.
"Is false"
Check failed as value evaluated to logical FALSE.
"Is NA."
Check failed as value evaluated to logical NA.
"Result is not a vector of mode logical."
Check failed as value evaluated to something other than a
logical vector.
"Resulting logical vector is not of length 1."
Check failed as value evaluated to logical vector, but either
it was empty (length 0) or it had more than one element.
"Checking expression for truth failed with the following error: ..."
Check failed unexpectedly with an error. This is probably a problem with
evaluating the provided expression.
-
checkIsFalse: Use to check if an expression (value)
evaluates to FALSE. Returns one of:
"" (empty string)
Check succeeded as value evaluated to logical FALSE.
"Is true."
Check failed as value evaluated to logical TRUE.
"Is NA."
Check failed as value evaluated to logical NA.
"Result is not a vector of mode logical."
Check failed as value evaluated to something other than a
logical vector.
"Resulting logical vector is not of length 1."
Check failed as value evaluated to logical vector, but either
it was empty (length 0) or it had more than one element.
"Checking expression for falsehood failed with the following error: ..."
Check failed unexpectedly with an error. This is probably a problem with
evaluating the provided expression.
Examples
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# Ensuring a value is NULL
checkIsNull( NULL )
#=> [1] ""
checkIsNull( NA )
#=> [1] "Is not null."
checkIsNull()
#=> [1] "Checking for null failed with the following error:
#=> argument \"value\" is missing, with no default"
# Testing a value for existence
checkIsNotNull( NA )
#=> [1] ""
checkIsNotNull( NULL )
#=> [1] "Is null."
checkIsNotNull()
#=> [1] "Checking for null failed with the following error:
#=> argument \"value\" is missing, with no default"
# Testing the length of a value.
checkLength( character(0) )
#=> [1] ""
checkLength( c(1, 2), minimumLength= 2 )
#=> [1] ""
checkLength( c(1, 2), minimumLength= 3 )
#=> [1] "Length is not between 3 and Inf."
checkLength( c(1, 2), max= 1 )
#=> [1] "Length is not between 0 and 1."
checkLength( c(1, 2), min= 2, max= 2 )
#=> [1] ""
checkLength( c(1, 2, 3), min= 2, max= 2 )
#=> [1] "Length is not 2."
checkLength( NULL )
#=> [1] "Bad parameter 'value'. Is null."
# Checking an expression for truth
checkIsTrue( TRUE )
#=> [1] ""
checkIsTrue( 1 + 1 == 2 )
#=> [1] ""
checkIsTrue({
x <- 1
y <- 1
x == y
})
checkIsTrue( FALSE )
#=> [1] "Is false."
checkIsTrue( FALSE == NA )
#=> [1] "Is NA."
checkIsTrue({ x <- c(T,T,F); all(x) })
#=> [1] "Is false."
checkIsTrue( c(T,T,T) )
#=> [1] "Resulting logical vector is not of length 1."
checkIsTrue( "true" )
#=> [1] "Result is not a vector of mode logical."
checkIsTrue( NULL )
#=> [1] "Result is not a vector of mode logical."
checkIsTrue( stop('Oops.') )
#=> [1] ""Checking expression for truth failed with the following error: Oops."
# Checking an expression for falsehood
checkIsFalse( TRUE )
#=> [1] ""
checkIsFalse( 1 + 1 == 3 )
#=> [1] ""
checkIsFalse({
x <- 1
y <- 2
x == y
})
checkIsFalse( TRUE )
#=> [1] "Is true"
checkIsFalse( TRUE == NA )
#=> [1] "Is NA."
checkIsFalse({ x <- c(T,T,F); any(x) })
#=> [1] "Is false."
checkIsFalse( c(F,F,F) )
#=> [1] "Resulting logical vector is not of length 1."
checkIsFalse( "false" )
#=> [1] "Result is not a vector of mode logical."
checkIsFalse( NULL )
#=> [1] "Result is not a vector of mode logical."
checkIsFalse( stop('Oops.') )
#=> [1] "Checking expression for falsehood failed with the following error: Oops."
jefferys/DataRepo documentation built on May 19, 2019, 3:58 a.m.
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Description Usage Arguments Details Value Functions Examples
Description
A check function test something about its first (required) parameter and returns either an empty string if the check succeeds or a non-empty string if the check fails. Even when a test fails due to an error, the error is caught and a message will be returned. The check functions described here test various properties of values.
Usage
1 2 3 4 5 6 7 8 9 | checkIsNull(value)
checkIsNotNull(value)
checkLength(value, minimumLength = 0, maximumLength = Inf)
checkIsTrue(value)
checkIsFalse(value)
|
Arguments
value |
A value to check. |
minimumLength |
The minimum length |
maximumLength |
The maximum length |
Details
Many of the these functions are simple wrappers around existing R functions. Note, calling any of these functions with an unused parameters will cause an actual error as that is thrown before the called function begins executing and hence can not be trapped and converted to a message by the called function.
Value
All functions return either an empty string if the check succeeds or a non-empty string if the check fails (including if checking causes an error.)
Functions
-
checkIsNull: Use to test if a value isNULL. Returns one of:"" (empty string)
valuewasNULL."Is not null."
valuewas something other thanNULL."Checking for null failed with the following error: ..."
-
checkIsNotNull: Use to test that a value is notNULL. Returns one of:"" (empty string)
valuewas something other thanNULL."Is null."
valuewasNULL."Checking for null failed with the following error: ..."
-
checkLength: Use to test that a value has a length betweenminimumLengthandmaximumLength, inclusive. By default checks that length is between0andInf, so you need to supply at least one of these two extra parameters to do anything useful. Returns one of:"" (empty string)
valuehad a length >= min and had a length <= max."Length is not between
minandmax."valuehad a length > max, or had a length < min (or both min and max were chosen poorly!)."Length is not
length."valuedid not have the specified length. This message is only given when max == min."Bad parameter 'value'. ..."
valueparameter. This probably means that the providedvaluewasNULL.checkLength(NULL)results in a failure string, contrary to R's very tolerant evaluation oflength(NULL)as0."Checking for length failed with the following error: ..."
-
checkIsTrue: Use to check if an expression (value) evaluates toTRUE. Returns one of:"" (empty string)
valueevaluated to logicalTRUE."Is false"
valueevaluated to logicalFALSE."Is NA."
valueevaluated to logicalNA."Result is not a vector of mode logical."
valueevaluated to something other than a logical vector."Resulting logical vector is not of length 1."
valueevaluated to logical vector, but either it was empty (length 0) or it had more than one element."Checking expression for truth failed with the following error: ..."
-
checkIsFalse: Use to check if an expression (value) evaluates toFALSE. Returns one of:"" (empty string)
valueevaluated to logicalFALSE."Is true."
valueevaluated to logicalTRUE."Is NA."
valueevaluated to logicalNA."Result is not a vector of mode logical."
valueevaluated to something other than a logical vector."Resulting logical vector is not of length 1."
valueevaluated to logical vector, but either it was empty (length 0) or it had more than one element."Checking expression for falsehood failed with the following error: ..."
Examples
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 | # Ensuring a value is NULL
checkIsNull( NULL )
#=> [1] ""
checkIsNull( NA )
#=> [1] "Is not null."
checkIsNull()
#=> [1] "Checking for null failed with the following error:
#=> argument \"value\" is missing, with no default"
# Testing a value for existence
checkIsNotNull( NA )
#=> [1] ""
checkIsNotNull( NULL )
#=> [1] "Is null."
checkIsNotNull()
#=> [1] "Checking for null failed with the following error:
#=> argument \"value\" is missing, with no default"
# Testing the length of a value.
checkLength( character(0) )
#=> [1] ""
checkLength( c(1, 2), minimumLength= 2 )
#=> [1] ""
checkLength( c(1, 2), minimumLength= 3 )
#=> [1] "Length is not between 3 and Inf."
checkLength( c(1, 2), max= 1 )
#=> [1] "Length is not between 0 and 1."
checkLength( c(1, 2), min= 2, max= 2 )
#=> [1] ""
checkLength( c(1, 2, 3), min= 2, max= 2 )
#=> [1] "Length is not 2."
checkLength( NULL )
#=> [1] "Bad parameter 'value'. Is null."
# Checking an expression for truth
checkIsTrue( TRUE )
#=> [1] ""
checkIsTrue( 1 + 1 == 2 )
#=> [1] ""
checkIsTrue({
x <- 1
y <- 1
x == y
})
checkIsTrue( FALSE )
#=> [1] "Is false."
checkIsTrue( FALSE == NA )
#=> [1] "Is NA."
checkIsTrue({ x <- c(T,T,F); all(x) })
#=> [1] "Is false."
checkIsTrue( c(T,T,T) )
#=> [1] "Resulting logical vector is not of length 1."
checkIsTrue( "true" )
#=> [1] "Result is not a vector of mode logical."
checkIsTrue( NULL )
#=> [1] "Result is not a vector of mode logical."
checkIsTrue( stop('Oops.') )
#=> [1] ""Checking expression for truth failed with the following error: Oops."
# Checking an expression for falsehood
checkIsFalse( TRUE )
#=> [1] ""
checkIsFalse( 1 + 1 == 3 )
#=> [1] ""
checkIsFalse({
x <- 1
y <- 2
x == y
})
checkIsFalse( TRUE )
#=> [1] "Is true"
checkIsFalse( TRUE == NA )
#=> [1] "Is NA."
checkIsFalse({ x <- c(T,T,F); any(x) })
#=> [1] "Is false."
checkIsFalse( c(F,F,F) )
#=> [1] "Resulting logical vector is not of length 1."
checkIsFalse( "false" )
#=> [1] "Result is not a vector of mode logical."
checkIsFalse( NULL )
#=> [1] "Result is not a vector of mode logical."
checkIsFalse( stop('Oops.') )
#=> [1] "Checking expression for falsehood failed with the following error: Oops."
|
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