%BQUOTE and %NRBQUOTE

%BQUOTE and %NRBQUOTE

Mask special characters and mnemonic operators in a resolved value at macro execution

Type: Macro quoting functions

See also:

%QUOTE and %NRQUOTE

%SUPERQ

Syntax
Details
Tip
Comparisons
Example
	Quoting a Variable

Syntax

%BQUOTE (character string | text expression)

%NRBQUOTE (character string | text expression)

Details

The %BQUOTE and %NRBQUOTE functions mask a character string or resolved value of a text expression during execution of a macro or macro language statement. They mask the following special characters and mnemonic operators:

' " ( ) + - * / < > = ¬ ^ ~ ; , blank
AND OR NOT EQ NE LE LT GE GT

In addition, %NRBQUOTE masks

& %

%NRBQUOTE is most useful when the resolved value of an argument may contain

strings that look like macro variable references but are not, so the macro processor should not attempt to resolve them when it next encounters them.
macro invocations that you do not want the macro processor to attempt to resolve when it next encounters them.

Tip

You can use %BQUOTE and %NRBQUOTE for all execution-time macro quoting because they mask all characters and mnemonic operators that can be interpreted as elements of macro language. Quotation marks ( ' ") and parentheses ( ( )) that do not have a match do not have to be marked.

For a description of quoting in SAS macro language, see Chapter 7, "Macro Quoting," in SAS Macro Language: Reference.

Comparisons

%BQUOTE and %NRBQUOTE do not require that you mark quotation marks and parentheses that do not have a match. However, the %QUOTE and %NRQUOTE functions do.
%NRBQUOTE and the %SUPERQ function mask the same items. However, %SUPERQ does not attempt to resolve a macro variable reference or a macro invocation that occurs in the value of the specfied macro variable. %NRBQUOTE does attempt to resolve such references.

Example

Example 1: Quoting a Variable

This example tests whether a filename passed to the macro FILEIT starts with a quotation mark. Based on that evaluation, the macro creates the correct FILE command.

%macro fileit(infile);
  %if %bquote(&infile) NE %then
     %do;
         %let char1 = %bquote(%substr(&infile,1,1));
         %if %bquote(&char1) = %str(%')
             or %bquote(&char1) = %str(%")
         %then %let command=FILE &infile;
         %else %let command=FILE "&infile";
     %end;
  %put &command;
%mend fileit;

%fileit(myfile)
%fileit('myfile')

Executing this program writes to the log:

FILE "myfile"
FILE 'myfile'

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