Macro variable not resolving to correct value

[kaziumair]

Hi everyone,

I have the following website url:

https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=0&ajax_count=1&cat_name=dm168&taxonomy_name=section

The above is the link to the first page of the website.

In order to go to the 2nd page the  load_offset value will be incremented by 21 and ajax_count value will change to 2.

So the link to the 2nd page will be

https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=21&ajax_count=2&cat_name=dm168&taxonomy_name=section

I am trying to implement the above logic to browse n number of pages, however I am finding it difficult to change the load_offset value.

Any suggestions on how I can get the correct load_offset value?

The code I am using :

option mprint mlogic symbolgen;
/*macro to extract multiple pages */
options dlcreatedir;
%let htmldir = %sysfunc(getoption(WORK))/html;
libname html "&htmldir.";
libname html clear;
%let page=0;
%macro getPages(num=);
 %do i = 1 %to &num.;
 	%if i=1 %then %do;
 		%let off=&page;
 	%end;
 	%if i gt 1 %then %do;
 		%let off=%sysevalf(&&i-1)*21);
 	%end;
 	%let url=https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost%str(&)lazy_load_offset=&off%str(&)ajax_count=&i%str(&)cat_name=dm168%str(&)taxonomy_name=section;
	filename dest "&htmldir./page&i..html";
	proc http
	url = "&url."
	out = dest
	method = "GET" ;
	run;
	%put &url &off &i;
%end;
%mend;



/*calling the macro*/
%getPages(num=2);

  Log:

1          OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;
 68         
 69         option mprint mlogic symbolgen;
 70         /*macro to extract multiple pages */
 71         options dlcreatedir;
 72         %let htmldir = %sysfunc(getoption(WORK))/html;
 73         libname html "&htmldir.";
 SYMBOLGEN:  Macro variable HTMLDIR resolves to 
             /saswork/SAS_workB9DF00015C53_odaws01-apse1.oda.sas.com/SAS_work869700015C53_odaws01-apse1.oda.sas.com/html
 NOTE: Library HTML was created.
 NOTE: Libref HTML was successfully assigned as follows: 
       Engine:        V9 
       Physical Name: /saswork/SAS_workB9DF00015C53_odaws01-apse1.oda.sas.com/SAS_work869700015C53_odaws01-apse1.oda.sas.com/html
 74         libname html clear;
 NOTE: Libref HTML has been deassigned.
 75         %let page=0;
 76         %macro getPages(num=);
 77          %do i = 1 %to &num.;
 78          %if i=1 %then %do;
 79          %let off=&page;
 80          %end;
 81          %if i gt 1 %then %do;
 82          %let off=%sysevalf(&&i-1)*21);
 83          %end;
 84          %let
 84       ! url=https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost%str(&)lazy_load_offset=&off%str(&)aja
 84       ! x_count=&i%str(&)cat_name=dm168%str(&)taxonomy_name=section;
 85         filename dest "&htmldir./page&i..html";
 86         proc http
 87         url = "&url."
 88         out = dest
 89         method = "GET" ;
 90         run;
 91         %put &url &off &i;
 92         %end;
 93         %mend;
 94         
 95         
 96         
 97         /*calling the macro*/
 98         %getPages(num=1);
 MLOGIC(GETPAGES):  Beginning execution.
 MLOGIC(GETPAGES):  Parameter NUM has value 1
 SYMBOLGEN:  Macro variable NUM resolves to 1
 MLOGIC(GETPAGES):  %DO loop beginning; index variable I; start value is 1; stop value is 1; by value is 1.  
 MLOGIC(GETPAGES):  %IF condition i=1 is FALSE
 MLOGIC(GETPAGES):  %IF condition i gt 1 is TRUE
 MLOGIC(GETPAGES):  %LET (variable name is OFF)
 SYMBOLGEN:  && resolves to &.
 SYMBOLGEN:  Macro variable I resolves to 1
 MLOGIC(GETPAGES):  %LET (variable name is URL)
 SYMBOLGEN:  Macro variable OFF resolves to 0*21)
 SYMBOLGEN:  Macro variable I resolves to 1
 SYMBOLGEN:  Macro variable HTMLDIR resolves to 
             /saswork/SAS_workB9DF00015C53_odaws01-apse1.oda.sas.com/SAS_work869700015C53_odaws01-apse1.oda.sas.com/html
 SYMBOLGEN:  Macro variable I resolves to 1
 MPRINT(GETPAGES):   filename dest 
 "/saswork/SAS_workB9DF00015C53_odaws01-apse1.oda.sas.com/SAS_work869700015C53_odaws01-apse1.oda.sas.com/html/page1.html";
 SYMBOLGEN:  Macro variable URL resolves to 
             https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=0*21)&ajax_count=1&cat_
             name=dm168&taxonomy_name=section
 SYMBOLGEN:  Some characters in the above value which were subject to macro quoting have been unquoted for printing.
 MPRINT(GETPAGES):   proc http url = 
 "https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=0*21)&ajax_count=1&cat_name=dm168&
 taxonomy_name=section" out = dest method = "GET" ;
 MPRINT(GETPAGES):   run;
 
 NOTE: PROCEDURE HTTP used (Total process time):
       real time           1.76 seconds
       user cpu time       0.03 seconds
       system cpu time     0.00 seconds
       memory              2158.90k
       OS Memory           25504.00k
       Timestamp           10/28/2021 03:29:38 PM
       Step Count                        24  Switch Count  3
       Page Faults                       0
       Page Reclaims                     1188
       Page Swaps                        0
       Voluntary Context Switches        35
       Involuntary Context Switches      0
       Block Input Operations            0
       Block Output Operations           104
       
 
 MLOGIC(GETPAGES):  %PUT &url &off &i
 SYMBOLGEN:  Macro variable URL resolves to 
             https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=0*21)&ajax_count=1&cat_
             name=dm168&taxonomy_name=section
 SYMBOLGEN:  Some characters in the above value which were subject to macro quoting have been unquoted for printing.
 SYMBOLGEN:  Macro variable OFF resolves to 0*21)
 SYMBOLGEN:  Macro variable I resolves to 1
 https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost&lazy_load_offset=0*21)&ajax_count=1&cat_name=dm168&t
 axonomy_name=section 0*21) 1
 MLOGIC(GETPAGES):  %DO loop index variable I is now 2; loop will not iterate again.
 MLOGIC(GETPAGES):  Ending execution.
 99         
 100        /* DATA work.links; */
 101        /* format date_searched ddmmyy10.; */
 102        /* length headline $ 500 ; */
 103        /* LENGTH string $ 550; */
 104        /* INFILE "&htmldir./*.html" LENGTH = recLen LRECL = 32767; */
 105        /* INPUT line $VARYING32767. recLen; */
 106        /* p=prxparse('/<h1>/'); */
 107        /* pos=prxmatch(p,line); */
 108        /* if pos gt 0 then do; */
 109        /* headline=substr(line,p); */
 110        /* end; */
 111        /* if pos not gt 0 then delete; */
 112        /* OUTPUT; */
 113        /* RUN; */
 114        /*  */
 115        /* data work.decodelinks(drop=rx1); */
 116        /* set work.links; */
 117        /* retain rx1 rx2; */
 118        /* rx1=prxparse("s/<.*?>//"); */
 119        /* call prxchange(rx1,-1,headline); */
 120        /* rx2=prxparse("s/&#\d+//"); */
 121        /* call prxchange(rx2,-1,headline); */
 122        /* run; */
 123        
 124        OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;
 SYMBOLGEN:  Macro variable GRAPHTERM resolves to GOPTIONS NOACCESSIBLE;
 134 

[PaigeMiller]

Since you have already done the work and turned on macro debugging options, show us the entire LOG for this code. Copy the log as text and paste it into the window that appears when you click on the </> icon here in SAS Communities, this will format the log properly to make it more readable.

[kaziumair]

Hi , 

I have added the log

Thanks and Regards,

Mohammad Umair Kazi

[Tom]

So you want a macro variable to use to set the value after &lazy_load_offset= in the URL?

Then start with a value of 0 and then increment by 21 each time through the loop.

%local off i ;
%let off=0;
%do i=1 %to #
  ....
  %let off=%eval(&off + 21);
%end;

[Tom]

Why did you set OFF to this value?

SYMBOLGEN:  Macro variable OFF resolves to 0*21)

You equation is wrong.  Also since you are doing integer arithmetic so you can use %EVAL().

%let off=%eval( (&i-1) * 21 );

What is the purpose of the PAGE macro variable?   Isn't that what I has? 

%macro getPages(num=);
%local i off ;
%do i = 1 %to &num.;
  %let off=%eval((&i-1)*21);
  %let url=https://www.dailymaverick.co.za/wp-admin/admin-ajax.php?action=ajaxCategoryPost%str(&)lazy_load_offset=&off%str(&)ajax_count=&i%str(&)cat_name=dm168%str(&)taxonomy_name=section;
filename dest "&htmldir./page&i..html";
proc http
  url = "&url."
  out = dest
  method = "GET" 
;
run;
%put &=i &=off &=url ;
%end;
%mend;