TripleEqualsSupport
Related Docs:
object TripleEqualsSupport
| package scalactic
Class used via an implicit conversion to enable two objects to be compared with
=== and !== with a Boolean result and an enforced type constraint between
two object types.
Class used via an implicit conversion to enable two objects to be compared with
=== and !== with a Boolean result and an enforced type constraint between
two object types. For example:
assert(a === b) assert(c !== d)
You can also check numeric values against another with a tolerance. Here are some examples:
assert(a === (2.0 +- 0.1)) assert(c !== (2.0 +- 0.1))
Class used via an implicit conversion to enable any two objects to be compared with
=== and !== with a Boolean result and no enforced type constraint between
two object types.
Class used via an implicit conversion to enable any two objects to be compared with
=== and !== with a Boolean result and no enforced type constraint between
two object types. For example:
assert(a === b) assert(c !== d)
You can also check numeric values against another with a tolerance. Here are some examples:
assert(a === (2.0 +- 0.1)) assert(c !== (2.0 +- 0.1))
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is
implicitly convertible to A, given an implicit Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is
implicitly convertible to A, given an implicit Equivalence[A].
The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
ConversionCheckedTripleEquals) and
overriden as non-implicit by the other subtraits in this package.
an Equivalence[A] type class to which the Constraint.areEqual method will delegate to determine equality.
an implicit conversion from B to A
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[A].
Provides a A CanEqual B for any two types A and B, enforcing the type constraint
that A must be a subtype of B, given an explicit Equivalence[B].
Provides a A CanEqual B for any two types A and B, enforcing the type constraint
that A must be a subtype of B, given an explicit Equivalence[B].
This method is used to enable the Explicitly DSL for
TypeCheckedTripleEquals by requiring an explicit Equivalance[B], but
taking an implicit function that provides evidence that A is a subtype of B.
The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
LowPriorityTypeCheckedConstraint (extended by
TypeCheckedTripleEquals), and
overriden as non-implicit by the other subtraits in this package.
an Equivalence[B] type class to which the Constraint.areEqual method
will delegate to determine equality.
evidence that A is a subype of B
an A CanEqual B instance whose areEqual method delegates to the
areEquivalent method of the passed Equivalence[B].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is
implicitly convertible to B, given an explicit Equivalence[B].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is
implicitly convertible to B, given an explicit Equivalence[B].
This method is used to enable the Explicitly DSL for
ConversionCheckedTripleEquals by requiring an explicit Equivalance[B], but
taking an implicit function that converts from A to B.
The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
LowPriorityConversionCheckedConstraint (extended by
ConversionCheckedTripleEquals), and
overriden as non-implicit by the other subtraits in this package.
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[B].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint
that B must be a subtype of A, given an explicit Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint
that B must be a subtype of A, given an explicit Equivalence[A].
This method is used to enable the Explicitly DSL for
TypeCheckedTripleEquals by requiring an explicit Equivalance[B], but
taking an implicit function that provides evidence that A is a subtype of B. For example, under TypeCheckedTripleEquals,
this method (as an implicit method), would be used to compile this statement:
def closeEnoughTo1(num: Double): Boolean = (num === 1.0)(decided by forgivingEquality)
The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
TypeCheckedTripleEquals) and
overriden as non-implicit by the other subtraits in this package.
evidence that B is a subype of A
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is
implicitly convertible to A, given an explicit Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that B is
implicitly convertible to A, given an explicit Equivalence[A].
This method is used to enable the Explicitly DSL for
ConversionCheckedTripleEquals by requiring an explicit Equivalance[A], but
taking an implicit function that converts from B to A. For example, under ConversionCheckedTripleEquals,
this method (as an implicit method), would be used to compile this statement:
def closeEnoughTo1(num: Double): Boolean = (num === 1.0)(decided by forgivingEquality)
The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
ConversionCheckedTripleEquals) and
overriden as non-implicit by the other subtraits in this package.
an Equivalence[A] type class to which the Constraint.areEqual method will delegate to determine equality.
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[A].
Converts to an CheckingEqualizer that provides === and !== operators
that result in Boolean and enforce a type constraint.
Converts to an CheckingEqualizer that provides === and !== operators
that result in Boolean and enforce a type constraint.
This method is overridden and made implicit by subtraits TypeCheckedTripleEquals and
ConversionCheckedTripleEquals, and overriden as
non-implicit by the other subtraits in this package.
the object whose type to convert to CheckingEqualizer.
NullPointerException if left is null.
Converts to an Equalizer that provides === and !== operators that
result in Boolean and enforce no type constraint.
Converts to an Equalizer that provides === and !== operators that
result in Boolean and enforce no type constraint.
This method is overridden and made implicit by subtrait TripleEquals and overriden as non-implicit by the other
subtraits in this package.
the object whose type to convert to Equalizer.
NullPointerException if left is null.
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is
implicitly convertible to B, given an implicit Equivalence[B].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint that A is
implicitly convertible to B, given an implicit Equivalence[B].
The returned Constraint's areEqual method uses the implicitly passed Equivalence[B]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
LowPriorityConversionCheckedConstraint (extended by
ConversionCheckedTripleEquals), and
overriden as non-implicit by the other subtraits in this package.
an implicit conversion from A to B
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[B].
Provides an A CanEqual B for any two types A and B, enforcing the type constraint
that A must be a subtype of B, given an implicit Equivalence[B].
Provides an A CanEqual B for any two types A and B, enforcing the type constraint
that A must be a subtype of B, given an implicit Equivalence[B].
The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
LowPriorityTypeCheckedConstraint (extended by
TypeCheckedTripleEquals), and
overriden as non-implicit by the other subtraits in this package.
an Equivalence[B] type class to which the Constraint.areEqual method
will delegate to determine equality.
evidence that A is a subype of B
an A CanEqual B instance whose areEqual method delegates to the
areEquivalent method of the passed Equivalence[B].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint
that B must be a subtype of A, given an implicit Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, enforcing the type constraint
that B must be a subtype of A, given an implicit Equivalence[A].
The returned Constraint's areEqual method uses the implicitly passed Equivalence[A]'s
areEquivalent method to determine equality.
This method is overridden and made implicit by subtraits
TypeCheckedTripleEquals) and
overriden as non-implicit by the other subtraits in this package.
evidence that B is a subype of A
an A CanEqual B instance whose areEqual method delegates to the areEquivalent method of
the passed Equivalence[A].
Provides an A CanEqual B instance for any two types A and B, with no type constraint enforced, given an
implicit Equality[A].
Provides an A CanEqual B instance for any two types A and B, with no type constraint enforced, given an
implicit Equality[A].
The returned Constraint's areEqual method uses the implicitly passed Equality[A]'s
areEqual method to determine equality.
This method is overridden and made implicit by subtraits TripleEquals and
overriden as non-implicit by the other subtraits in this package.
an Equality[A] type class to which the Constraint.areEqual method will delegate to determine equality.
an A CanEqual B instance whose areEqual method delegates to the areEqual method of
the passed Equality[A].
Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate
the “<left> should !== (<pivot> +- <tolerance>)”
syntax of Matchers.
Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate
the “<left> should !== (<pivot> +- <tolerance>)”
syntax of Matchers.
the Spread[T] against which to compare the left-hand value
a TripleEqualsInvocationOnSpread wrapping the passed Spread[T] value, with
expectingEqual set to false.
Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate
the “<left> should !== null” syntax
of Matchers.
Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate
the “<left> should !== null” syntax
of Matchers.
a null reference
a TripleEqualsInvocation wrapping the passed null value, with expectingEqual
set to false.
Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate
the “<left> should !== <right>” syntax
of Matchers.
Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate
the “<left> should !== <right>” syntax
of Matchers.
the right-hand side value for an equality assertion
a TripleEqualsInvocation wrapping the passed right value, with expectingEqual
set to false.
Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate
the “<left> should === (<pivot> +- <tolerance>)”
syntax of Matchers.
Returns a TripleEqualsInvocationOnSpread[T], given an Spread[T], to facilitate
the “<left> should === (<pivot> +- <tolerance>)”
syntax of Matchers.
the Spread[T] against which to compare the left-hand value
a TripleEqualsInvocationOnSpread wrapping the passed Spread[T] value, with
expectingEqual set to true.
Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate
the “<left> should === null” syntax
of Matchers.
Returns a TripleEqualsInvocation[Null], given a null reference, to facilitate
the “<left> should === null” syntax
of Matchers.
a null reference
a TripleEqualsInvocation wrapping the passed null value, with expectingEqual
set to true.
Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate
the “<left> should === <right>” syntax
of Matchers.
Returns a TripleEqualsInvocation[T], given an object of type T, to facilitate
the “<left> should === <right>” syntax
of Matchers.
the right-hand side value for an equality assertion
a TripleEqualsInvocation wrapping the passed right value, with expectingEqual
set to true.
Returns an Equality[A] for any type A that determines equality
by first calling .deep on any Array (on either the left or right side),
then comparing the resulting objects with ==.
Returns an Equality[A] for any type A that determines equality
by first calling .deep on any Array (on either the left or right side),
then comparing the resulting objects with ==.
a default Equality for type A
Trait that defines abstract methods used to enforce compile-time type constraints for equality comparisons, and defines
===and!==operators used by matchers.The abstract methods of this trait are selectively implemented as implicit by subclasses to enable a spectrum of type constraints for the
===and!==operators. As an illustration, if in the expression,a === b, the type ofaisAandbisB, the following three levels of compile-time checking can be obtained fromTripleEqualsSupportsubtraits:Unchecked -
AandBcan be any two types. This constraint level is available from subtraitTripleEquals.Statically-checked -
Amust be a subtype ofB, or vice versa, or must cooperate such that the equality laws stated in theequalscontract are preserved. This (intermediate) constraint level is available by using subtraitTripleEqualsand installing the SuperSafe Community Edition Scala compiler plugin.Type-checked -
Amust be a subtype ofB, or vice versa. (BothAandBcan be the same type, because a type is considered a subtype of itself.) This (strongest) constraint level is available from subtraitTypeCheckedTripleEquals.This trait defines all methods that need to be defined implicitly by the subtraits so that if multiple subtraits are used together, the inner-most subtrait in scope can not only enable the implicits it needs by overriding or hiding those methods (currently-in-scope as regular, non-implicit methods) and making them implicit, it can also disable any implicits enabled by its sibling subtraits in enclosing scopes. For example, if your test class mixes in
TypeCheckedTripleEquals, inside your test class the following methods will be implicit:convertToCheckingEqualizertypeCheckedConstraintlowPriorityTypeCheckedConstraintconvertEquivalenceToAToBConstraintconvertEquivalenceToBToAConstraintIf in the body of a test you want to turn off the type checking, you can import the members of
TripleEqualsin the body of that test. This will not only hide non-implicit methodsconvertToEqualizerunconstrainedEqualityofTypeCheckedTripleEquals, replacing those with implicit ones defined inTripleEquals, it will also hide the three methods made implicit inTypeCheckedTripleEquals(and listed above), replacing them by non-implicit ones.In short, you should be able to select a primary constraint level via either a mixin or import, then change that in nested scopes however you want, again either through a mixin or import, without getting any implicit conversion ambiguity. The innermost constraint level in scope will always be in force.