<boolean>

The class of boolean values.

The literal constants #t and #f are general instances of <boolean>.  Note that for the purposes of conditional expressions, all objects besides #f count as true.

Exported from

Modifiers

abstract free sealed

Superclasses

Subclasses

Functions on <boolean>

Functions returning <boolean>

The common-dylan module.
Whenever possible, we have tried to keep the Dylan module pristine and unextended, preferring to add our extensions to separate modules or libraries.
The class of all Dylan objects.
A class.
A class.
A function for building hash functions that test collection equivalence.
Convert an integer to the corresponding digit.
Converts an integer to a string value.
There are two unrelated print functions.
Creates a string that contains a printed object representation.
A function.
Runs an application in a separate process.
There are two unrelated functions named split.
Logical negation.
Compares two objects for inequality.
Compares two objects for nonidentity.
Returns true if its first operand is less than its second operand.
Returns true if its first operand is less than or equal to its second operand.
Compares two objects for identity.
A function.
Returns #t if the character is in [a-zA-Z].
Returns #t if the character is alphabetic or a digit.
Tests if a function is applicable to sample arguments.
A function.
Returns #t if the character is an ASCII character.
Tests whether two objects have the same string value aside from case.
Returns #t if the character is not printable.
Returns #t if the character is a numeric digit [0-9].
A generic function.
A generic function.
A generic function.
Returns true if its argument is empty.
A generic function.
Returns true if its argument is an even number.
Returns true if a predicate returns true when applied to all corresponding elements of a set of collections.
A generic function.
Returns true if an object is not equal to $unfound, and false otherwise.
A generic function.
Returns information about the arguments accepted by a function.
Returns #t if the character is a graphic character (a printing, non-whitespace character).
Returns #t if the character is a hexadecimal digit.
A function.
Returns true if object is a general instance of type.
Returns true if its argument is an integer.
Returns #t if a key is in a collection.
Check whether this sequence is a <list>.
A function.
A generic function.
Tests the value of a particular bit in its argument.
Returns #t if the character is in [a-z].
Returns true if collection contains value as determined by test.
Returns true if its argument is negative.
Returns true if its argument is an odd number.
Tests whether an option was present on the command-line.
Determine whether an option was present, given a corresponding option name.
Tests whether an exclusive lock has been claimed by the current thread.
Check whether this sequence is a <pair>.
Like do, except that it takes multiple argument lists.
Parses a list of command-line arguments.
Returns true if its argument is positive.
Verifies that one element comes before another in a sequence.
Returns #t if the character is printable (a graphic or whitespace character).
Returns #t if the character is punctuation (a graphic, non-alphanumeric character).
Reads in one line of elements from the stream starting from the stream’s current position.
Reads a line of elements from a stream into a collection.
Reads in a group of elements from a stream up to and including a marker element.
Reads in a group of elements from a stream up to but not including a marker element.
Modifies collection so that it no longer has a key equal to key.
Returns true if a condition’s recovery protocol allows returning values.
A function that signals an event created by create-application-event.
A generic function.
A generic function.
Tests whether a slot has been initialized.
Checks to see if the stream is at the end of its contents.
Checks if the stream is available for reading.
A generic function.
Checks to see if a stream is open.
Returns true if type1 is a subtype of type2.
Returns true if its argument, the keyword argument of a function, is not the unique “unsupplied” value, and false if it is.
A generic function.
A generic function.
Returns true if its argument is equal to the unique “unfound” value, $unfound, and false if it is not.
Returns true if its argument is equal to the unique “unsupplied” value, and false if it is not.
Blocks until a synchronization object is available.
Halt the current thread until an event is signaled or a timeout expires.
Returns #t if the character is whitespace (space, tab, linefeed, or newline).
Returns true if its argument is equal to zero.