SAS 9.4 Macro Language: Reference, Fourth Edition, 4th Edition

You must use %NRSTR to mask the % sign at compilation, so the macro processor does

not try to invoke %NRSTR a second time. If you did not use %NRSTR to mask the

string %nrstr, the macro processor would complain about a missing open parenthesis

for the function.

%BQUOTE and %NRBQUOTE Functions

Using %BQUOTE and %NRBQUOTE Functions

%BQUOTE and %NRBQUOTE mask values during execution of a macro or a macro

language statement in open code. These functions instruct the macro processor to resolve

a macro expression as far as possible and mask the result, issuing any warning messages

for macro variable references or macro invocations that it cannot resolve. These

functions mask all the characters that %STR and %NRSTR mask with the addition of

unmarked percent signs; unmatched, unmarked single and double quotation marks; and

unmatched, unmarked opening and closing parentheses. That means that you do not have

to precede an unmatched quotation mark with a % sign, as you must when using %STR

and %NRSTR.

The %BQUOTE function treats all parentheses and quotation marks produced by

resolving macro variable references or macro calls as special characters to be masked at

execution time. (It does not mask parentheses or quotation marks that are in the

argument at compile time.) Therefore, it does not matter whether quotation marks and

parentheses in the resolved value are matched; each one is masked individually.

The %NRBQUOTE function is useful when you want a value to be resolved when first

encountered, if possible, but you do not want any ampersands or percent signs in the

result to be interpreted as operators by an %EVAL function.

If the argument of the %NRBQUOTE function contains an unresolvable macro variable

reference or macro invocation, the macro processor issues a warning message before it

masks the ampersand or percent sign (assuming the SERROR or MERROR system

option, described in “System Options for Macros” on page 343 is in effect). To suppress

the message for unresolved macro variables, use the %SUPERQ function (discussed

later in this section) instead.

The %BQUOTE and %NRBQUOTE functions operate during execution and are more

flexible than %STR and %NRSTR. Therefore, %BQUOTE and %NRBQUOTE are

good choices for masking strings that contain macro variable references.

Examples Using %BQUOTE

In the following statement, the %IF-%THEN statement uses %BQUOTE to prevent an

error if the macro variable STATE resolves to OR (for Oregon), which the macro

processor would interpret as the logical operator OR otherwise:

%if %bquote(&state)=%str(OR) %then %put Oregon Dept. of

Revenue;

Note: This example works if you use %STR, but it is not robust or good programming

practice. Because you cannot guarantee what &STATE is going to resolve to, you

need to use %BQUOTE to mask the resolution of the macro variable at execution

time, not the name of the variable itself at compile time.

In the following example, a DATA step creates a character value containing a single

quotation mark and assigns that value to a macro variable. The macro READIT then uses

%BQUOTE and %NRBQUOTE Functions 89