It is also possible to nest
| Gloss |
|---|
| PreSpace | false |
|---|
| t | expressions |
|---|
|
, one inside the other. Any valid
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expression |
|---|
|
may be enclosed in a pair of brackets, and included as the value of an attribute in another
. For example, the following
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expression |
|---|
|
describes a medication product that has a single dose form, which is both a spray and a suspension:
...
In the example above, note the use of round brackets (i.e. "( )") to identify a nested
, as opposed to braces (i.e. "{ }"), which is used to identify attribute groups.
The following examples show how complex
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expressions |
|---|
|
may be build up from simple ones, a layer at a time. This first
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expression |
|---|
|
describes a left hip structure:
...
This next expression uses the "left hip"
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expression |
|---|
|
above to describe a procedure to replace it:
...
Applying a further grouped
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | refinement |
|---|
|
to the above describes a procedure to replace a left hip by inserting a prosthesis. Note that this example mixes an ungrouped qualification and a grouped qualification. Where this is done, the canonical representation of the expression includes all ungrouped attributes before the grouped ones (see
Terminology Services Guide for more details). Please also note that in the previous version of this standard a comma was not permitted between the last ungrouped attribute and the first attribute group – however this comma is now optional to avoid unexpected syntax errors.
| Scg expression |
|---|
| Border | ridge |
|---|
| ShowFormat | block |
|---|
|
397956004|Prosthetic arthroplasty of the hip|:
405814001|Procedure site - indirect| = (24136001|Hip joint structure|: 272741003|Laterality| = 7771000|Left|),
{ 363699004|Direct device| = 304120007|Total hip replacement prosthesis|,
260686004|Method| = 425362007|Surgical insertion - action|} |
Finally, the above
| Gloss |
|---|
| SpacePreSpace | truefalse |
|---|
| t | expression |
|---|
|
may be included within a contextual wrapper, to describe a procedure that has been performed on a patient to replace a left hip by inserting a prosthesis.
...