This section contains some basic examples that show what SCA can
do to help you with your programs. The examples have very little
explanation. For a more detailed explanation of the underlying
concepts, see the Basic_Query_Concepts help topic. The remainder
of this section is written in terms that are specific to BLISS
programs.
If you want to follow along and try the examples, you will need to
have an SCA library available. If you do not know how to create
an SCA library, read the Building_An_SCA_Library help topic. The
examples use generic variable names (such as i). You will have to
substitute variable names that actually exist in your code when
trying the examples.
The first example is the easiest query. It lets you find all the
items in your SCA library named i, and shows you all the places
where they appear (all occurrences of i):
FIND i
You can search for any name in this manner, including using
wildcard characters (for example, FIND i*).
Now suppose you are looking for an occurrence, and you know that
it occurs in a particular file. The following query finds all
occurrences of items that are named i, but will then limit them to
those that happen to occur in the file named PROG.B32.
FIND i AND FILE_SPEC="PROG.B32"
Another typical question you might ask is, "Find all the places
where this item is assigned to (or read from, called, declared and
so forth)." The next example finds all occurrences of items that
are named i, but then limits them to only those occurrences where
i is assigned a value:
FIND i AND OCCURRENCE=WRITE
(SCA understands many occurrence classes other then WRITE. See the
help subtopics under Getting_Started for tables containing all the
SCA attributes and their corresponding meanings in BLISS.)
Often, you only want to know where (in what file or module) a
particular routine is, so that you can go to it and edit it. You
can use the first query (where i will be the name of the routine)
and then look through the output. The output will include all
occurrences of the routine, one of which will be its declaration,
which you can then select. Or, you can ask SCA to limit the search
for you by typing the following query:
FIND i AND OCCURRENCE=PRIMARY
In SCA terms, a primary declaration is the most significant
declaration of an item. For a BLISS routine, this means the
place where the routine is actually implemented. This is in
contrast to FORWARD or EXTERNAL declarations, which are associated
declarations.
Another problem you might have is that there are many different
items in your system having a given name. Some may be variables;
others may be routines, literals, macros, and so forth. Suppose
you want to find only the routines named i. Again, the query
FIND i will give you what you wanted, but it will also give you
much more. It is preferable to issue the following query:
FIND i AND SYMBOL_CLASS=ROUTINE
The last four examples have all selected information based on two
attributes. The last example selected information based on a name
attribute (in this case, i) and a symbol_class attribute (in this
case, ROUTINE). Note how the attributes are combined using the
boolean operator AND. In general, you can select items out of your
library based on any combination of attributes, using AND as well
as the other logical operators OR, XOR, and NOT.
The next example shows another primary feature of SCA - the
ability to display relationships between items. This example shows
the most common use of this feature. It finds the complete call
tree (that is, all routines called directly and indirectly) of the
routine named i.
FIND CALLED_BY (i, DEPTH=ALL)
If you want to limit the depth of the call tree, replace the
keyword ALL by any positive integer.
The final part of this section describes how to go directly to the
source code once you have issued a query. After issuing the query
FIND i, for example, you can have an LSE query buffer containing
something that looks like the following:
I variable
BLISS_MODULE\60 LOCAL declaration
BLISS_MODULE\75 write reference
BLISS_MODULE\79 read reference
BLISS_MODULE\122 read reference
BLISS_MODULE\144 write reference
BLISS_MODULE\146 read reference
BLISS_MODULE\149 write reference
BLISS_MODULE\149 read reference
BLISS_MODULE\150 read reference
BLISS_MODULE\166 read reference
The first two lines of this display will be highlighted. The first
line represents the item you looked for (i), and the rest of the
lines represent the different places in the code where this item
occurred (that is, the occurrences of i). By using the up and down
arrows on your keyboard, or by clicking on an occurrence with your
mouse, you can choose the occurrence you want to see. Then, type
CTRL/G (the keyboard equivalent of the GOTO SOURCE command) and
LSE will bring the source file into a buffer and position you at
the occurrence you chose.
To obtain help on the following topics, request help as indicated.
o For help on query language, see the Basic_Query_Concepts help
topic.
o For help on libraries, see the Building_An_SCA_Library help
topic.