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ANSI Common Lisp  26 Glossary 26.1 Glossary
T
- t:
- n.
1. a. the boolean representing true.
b. the canonical generalized boolean representing true.
(Although any object other than nil is considered true
as a generalized boolean,
t is generally used when there is no special reason to prefer one
such object over another.)
2. the name of the type to which all objects belong - the
supertype of all types (including itself).
3. the name of the superclass of all classes except itself.
- tag:
- n.
1. a catch tag.
2. a go tag.
- tail:
- n. (of a list)
an object that is the same as either some cons
which makes up that list or the atom (if any) which terminates
the list.
The empty list is a tail of every proper list.
- target:
- n.
1. (of a constructed stream)
a constituent of the constructed stream.
The target of a synonym stream is
the value of its synonym stream symbol.
2. (of a displaced array)
the array to which the displaced array is displaced.
(In the case of a chain of constructed streams or displaced arrays,
the unqualified term "target" always refers to the immediate
target of the first item in the chain, not the immediate target
of the last item.)
- terminal I/O:
- n.
the bidirectional stream
that is the value of the variable *terminal-io*.
- terminating:
- n. (of a macro character)
being such that, if it appears while parsing a token, it terminates that token.
See Section 2.2 Reader Algorithm.
- tertiary value:
- n. (of values resulting from the
evaluation of a form)
the third value, if any,
or else nil if there are fewer than three values.
- throw:
- v.
to transfer control and values to a catch.
See the special operator throw.
- tilde:
- n. the standard character that is called "tilde" (~).
See Figure 2.1.3 Standard Characters.
- time:
-
a representation of a point (absolute time)
or an interval (relative time)
on a time line.
See decoded time, internal time, and universal time.
- time zone:
- n. a rational multiple of 1/3600 between -24 (inclusive)
and 24 (inclusive) that represents a time zone as a number of hours
offset from Greenwich Mean Time. Time zone values increase with motion to the west,
so Massachusetts, U.S.A. is in time zone 5,
California, U.S.A. is time zone 8,
and Moscow, Russia is time zone -3.
(When "daylight savings time" is separately represented
as an argument or return value, the time zone
that accompanies it does not depend on whether daylight savings time
is in effect.)
- token:
- n. a textual representation for a number or a symbol.
See Section 2.3 Interpretation of Tokens.
- top level form:
- n.
a form which is processed specially by compile-file for
the purposes of enabling compile time evaluation of that
form.
Top level forms include those forms which
are not subforms of any other form,
and certain other cases. See Section 3.2.3.1 Processing of Top Level Forms.
- trace output:
- n.
the output stream which is the value of the dynamic variable
*trace-output*.
- tree:
- n.
1. a binary recursive data structure made up of conses and
atoms: the conses are themselves also trees
(sometimes called "subtrees" or "branches"), and the atoms
are terminal nodes (sometimes called leaves). Typically,
the leaves represent data while the branches establish some
relationship among that data.
2. in general, any recursive data structure that has some notion of
"branches" and leaves.
- tree structure:
- n. (of a tree1)
the set of conses that make up the tree.
Note that while the car1b component of each such cons
is part of the tree structure,
the objects that are the cars2 of each cons
in the tree
are not themselves part of its tree structure
unless they are also conses.
- true:
- n.
any object
that is not false
and that is used to represent the success of a predicate test.
See t1.
- truename:
- n.
1. the canonical filename of a file in the file system.
See Section 20.1.3 Truenames.
2. a pathname representing a truename1.
- two-way stream:
- n.
a stream of type two-way-stream,
which is a bidirectional composite stream that
receives its input from an associated input stream
and sends its output to an associated output stream.
- type:
- n.
1. a set of objects, usually with common structure, behavior, or purpose.
(Note that the expression "X is of type Sa"
naturally implies that "X is of type Sb" if
Sa is a subtype of Sb.)
2. (immediately following the name of a type)
a subtype of that type.
The type vector is an array type.
- type declaration:
- n.
a declaration that asserts that every reference to a
specified binding within the scope of the declaration
results in some object of the specified type.
- type equivalent:
- adj. (of two types X and Y)
having the same elements;
that is, X is a subtype of Y
and Y is a subtype of X.
- type expand:
- n. to fully expand a type specifier, removing any references to
derived types. (Common Lisp provides no program interface to cause
this to occur, but the semantics of Common Lisp are such that every
implementation must be able to do this internally, and some
situations involving type specifiers are most easily described
in terms of a fully expanded type specifier.)
- type specifier:
- n.
an expression that denotes a type.
The symbol random-state, the list (integer 3 5),
the list (and list (not null)), and the class named
standard-class are type specifiers.
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