Read XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition Online
Authors: Michael Kay
XSLT 2.0 and XPath 2.0 Programmer's Reference, 4th Edition (542 page)
.
See Also
The Type Matching Rules
on page 219 in Chapter 5
dateTime
This function constructs an
xs:dateTime
value from a supplied
xs:date
and
xs:time
.
Signature
| Argument | Type | Meaning |
| date | xs:date? | A supplied date |
| time | xs:time? | A supplied time |
| Result | xs:dateTime? | The xs:dateTime formed by combining the supplied date and time |
Effect
If either of the arguments is an empty sequence, the result is an empty sequence.
Otherwise, the result is formed by combining the supplied date and time.
If neither of the arguments includes a timezone, the result will not include a timezone. If one of the arguments includes a timezone and the other does not, or if both include the same timezone, the result will have this timezone. If the two arguments both contain timezones and they are different, then an error occurs.
Note that the time value
24:00:00
is considered to represent exactly the same value as00:00:00(that is, midnight), and this is treated as the start of the day rather than the end.
Examples
| Expression | Result |
| dateTime(xs:date(‘2008-01-01’), xs:time(‘12:00:00’)) | 2008-01-01T12:00:00 |
| dateTime(xs:date(‘2008-01-01’), xs:time(‘12:00:00Z’)) | 2008-01-01T12:00:00Z |
| dateTime(xs:date(‘2008-01-01Z’), xs:time(‘12:00:00Z’)) | 2008-01-01T12:00:00Z |
| dateTime(xs:date(‘2008-01-01+02:00’), xs:time(‘12:00:00Z’)) | Error (different timezones) |
| dateTime(xs:date(‘2008-01-01+02:00’), xs:time(‘24:00:00’)) | 2008-01-01T00:00:00+02:00 |
See Also
current-date()
,
-dateTime()
,
-time()
on page 738
format-date()
,
-dateTime()
,
-time()
on page 781
day-from-date, day-from-dateTime
These two functions extract the day-of-the-month component from an
xs:date
or
xs:dateTime
value. For example, on Christmas Dayday-from-date(current-date())returns 25.
Signature
| Argument | Type | Meaning |
| input | xs:date? or xs:dateTime? | The value from which a component is to be extracted. The type of the supplied argument must correspond to the type implied by the function name. |
| Result | xs:integer? | The day, in the range 1-31 . |
Effect
The function returns the day component of the supplied
xs:date
or
xs:dateTime
. The value is used in its local timezone (not normalized to UTC). If the argument is an empty sequence, the result is an empty sequence.
Examples
| Expression | Result |
| day-from-date(xs:date(“2008-02-28”)) | 28 |
| day-from-dateTime(xs:dateTime(“2008-02-28T13:00:00”)) | 28 |
| day-from-date(xs:date(“2008-07-31+01:00”)) | 31 |
| day-from-dateTime(xs:dateTime(“2008-07-31T23:00:00-05:00”)) | 31 |
See Also
current-date()
,
-dateTime()
,
-time()
on page 738
format-date()
,
-dateTime()
,
-time()
on page 781
month-from-date()
,
-dateTime()
on page 833
year-from-date()
,
-dateTime()
on page 911
days-from-duration
This function extracts the value of the days component from a normalized
xs:duration
value.
Signature
| Argument | Type | Meaning |
| input | xs:duration? | The duration whose days component is to be extracted. If an empty sequence is supplied, an empty sequence is returned. |
| Result | xs:integer? | The days component . |
Effect
The function returns the days component of the supplied
xs:duration
. The duration value is first normalized so that the number of hours is less than 24, the number of minutes is less than 60, and so on. However, there is never any conversion of days to months or vice versa. The result will be negative if the duration is negative.
Examples
| Expression | Result |
| days-from-duration(xs:duration(“P5DT12H”)) | 5 |
| days-from-duration(xs:dayTimeDuration(“PT72H”)) | 3 |
| days-from-duration(xs:dayTimeDuration(“-P1D”)) | -1 |
| days-from-duration(xs:yearMonthDuration(“P1 M”)) | 0 |
See Also
hours-from-duration
on page 801
minutes-from-duration
on page 832
seconds-from-duration
on page 874
deep-equal
The
deep-equal()
function performs a deep comparison between two sequences:
- The items in corresponding positions in each sequence must be deep-equal to each other.
- If the items are nodes, they are compared by examining their children and attributes recursively.
Signature
| Argument | Type | Meaning |
| sequence-1 | item()* | The first operand of the comparison |
| sequence-2 | item()* | The second operand of the comparison |
| collation (optional) | xs:string | The collation to be used for comparing strings (at any depth) |
| Result | xs:boolean | True if the sequences are deep-equal; otherwise, false |
Effect
This function may be used to compare:
- Two nodes, to see whether the subtrees rooted at those nodes have identical content at every level
- Two sequences, to see whether the items they contain are pairwise deep-equal
The function is therefore defined to operate on sequences, though in many cases it will be used to compare two singleton element or document nodes.
At the top level, two sequences are deep-equal if they have the same number of items, and if each item in the first sequence is deep-equal to the item in the corresponding position of the other sequence. A consequence of this rule is that an empty sequence is deep-equal to another empty sequence.
Where the item in a sequence is an atomic value, the corresponding item in the other sequence must also be an atomic value, and they must compare as equal using theeqoperator, using the specified
collation
if they are strings, URIs, or untyped atomic values. If two items in corresponding positions are not comparable (for example, if one is an integer and the other is a string, or if one is a date and the other is an element node), then the function returns false; it does not report an error. Nodes are not atomized. NaN is considered to be equal to itself.
