'a' vs. %str(%')a%str(%')

yuguo — Fri, 19 Jun 2015 18:13:32 GMT

This is largely a theoretical question about macro variables. I have two macro variables, v1 and v2. Both contain 3 characters consisting of 'a' (e.g. a single quote, the lowercase letter a, and the ending single quote). If you test their values, you'll find that they are equal:

dm log 'clear'; dm output 'clear';

option symbolgen mlogic mprint;

%macro myMacro;

%let v1='a';

%let v2=%str(%')a%str(%');

%if &v1=&v2 %then %put 1; %else %put 0;

%mend;

%myMacro

Log:

1 dm log 'clear'; dm output 'clear';

2 option symbolgen mlogic mprint;

4 %macro myMacro;

5 %let v1='a';

6 %let v2=%str(%')a%str(%');

7 %if &v1=&v2 %then %put 1; %else %put 0;

8 %mend;

9 %myMacro

MLOGIC(MYMACRO): Beginning execution.

MLOGIC(MYMACRO): %LET (variable name is V1)

MLOGIC(MYMACRO): %LET (variable name is V2)

SYMBOLGEN: Macro variable V1 resolves to 'a'

SYMBOLGEN: Macro variable V2 resolves to 'a'

SYMBOLGEN: Some characters in the above value which were subject to macro quoting have been

unquoted for printing.

MLOGIC(MYMACRO): %IF condition &v1=&v2 is TRUE

MLOGIC(MYMACRO): %PUT 1

MLOGIC(MYMACRO): Ending execution.

However, these 2 macro variables are different as illustrated in the next program:

data test;

x='a'; y=1; output;

x='b'; y=2; output;

run;

/*macro - this works*/

%let v1='a';

proc sql;

select * from test

where x=&v1;

quit;

/*macro2 - this doesn't work*/

%let v2=%str(%')a%str(%');

proc sql;

select * from test

where x=&v2;

quit;

%put _all_;

This is the log:

20 data test;

21 x='a'; y=1; output;

22 x='b'; y=2; output;

23 run;

NOTE: The data set WORK.TEST has 2 observations and 2 variables.

NOTE: DATA statement used (Total process time):

real time 0.07 seconds

cpu time 0.04 seconds

25 /*macro - this works*/

26 %let v1='a';

27 proc sql;

28 select * from test

29 where x=&v1;

SYMBOLGEN: Macro variable V1 resolves to 'a'

30 quit;

NOTE: PROCEDURE SQL used (Total process time):

real time 0.09 seconds

cpu time 0.06 seconds

32 /*macro2 - this doesn't work*/

33 %let v2=%str(%')a%str(%');

34 proc sql;

35 select * from test

36 where x=&v2;

SYMBOLGEN: Macro variable V2 resolves to 'a'

SYMBOLGEN: Some characters in the above value which were subject to macro quoting have been

unquoted for printing.

NOTE: Line generated by the macro variable "V2".

1 'a'

200

ERROR 22-322: Syntax error, expecting one of the following: a name, a quoted string,

a numeric constant, a datetime constant, a missing value, (, *, +, -, ALL, ANY,

BTRIM, CALCULATED, CASE, INPUT, PUT, SELECT, SOME, SUBSTRING, TRANSLATE, USER.

ERROR 200-322: The symbol is not recognized and will be ignored.

37 quit;

NOTE: The SAS System stopped processing this step because of errors.

NOTE: PROCEDURE SQL used (Total process time):

real time 0.01 seconds

cpu time 0.03 seconds

39 %put _all_;

GLOBAL SQLOBS 0

GLOBAL V2 a

GLOBAL SQLOOPS 0

GLOBAL SYS_SQL_IP_ALL -1

GLOBAL SYS_SQL_IP_STMT

GLOBAL SQLXOBS 0

GLOBAL SQLRC 8

GLOBAL SQLEXITCODE 0

GLOBAL V1 'a'

AUTOMATIC AFDSID 0

AUTOMATIC AFDSNAME

In the log generated by %put _all_, the macro variable v2 has some garbage (e.g. delta characters).

Here's is my question. The value of the macro variable v2 is actually different from 'a'. This is a deliberate design by SAS or a bug?%

Re: 'a' vs. %str(%')a%str(%')

Astounding — Fri, 19 Jun 2015 18:38:18 GMT

SQL is notorious for failing to unquote characters in time to parse them correctly. The most common application is passing a password to SQL, but the solution is straightforward in any event:

where x=%unquote(&v2);

That should handle the problem.

Re: 'a' vs. %str(%')a%str(%')

FriedEgg — Fri, 19 Jun 2015 18:46:17 GMT

This is deliberate and a effect of the use of macro-quoting.

%let m=%str(%')M%str(%');

proc sql;

/* will not work */ select count(*) from sashelp.class where sex=&m.;

/* will work */ select count(*) from sashelp.class where sex=%unquote(&m.);

quit;

topic Re: 'a' vs. %str(%')a%str(%') in SAS Programming

'a' vs. %str(%')a%str(%')

Re: 'a' vs. %str(%')a%str(%')

Re: 'a' vs. %str(%')a%str(%')