execstr

Arguments

instr

vector of character strings, Scilab instruction to be executed.

ierr

integer, 0 or error number.

msg

character string with values 'm' or 'n'. Default value is 'n'.

Description

Executes the Scilab instructions given in argument instr.

Note that instr should not make use of continuation marks (..)

If the 'errcatch' flag is not present, error handling works as usual.

If the 'errcatch' flag is set, and an error is encountered while executing the instructions defined in instr, execstr issues no error message, but aborts execution of the instr instructions (at the point where the error occurred), and resumes with ierr equal to the error number. In this case the display of the error message is controlled by the msg option:

"m"

error message is displayed and recorded.

"n"

no error message is displayed, but the error message is recorded (see lasterror). This is the default.

ierr=execstr(instr,'errcatch') can handle syntactical errors. This is useful for evalution of instruction obtained by a query to the user.

Examples

execstr('a=1') // sets a=1.
execstr('1+1') // does nothing (while evstr('1+1') returns 2)

execstr(['if %t then';
         '  a=1';
         '  b=a+1';
         'else'
         ' b=0'
         'end'])

execstr('a=zzzzzzz','errcatch')
execstr('a=zzzzzzz','errcatch','m')

//syntax errors
execstr('a=1?02','errcatch')
lasterror(%t)

execstr('a=[1 2 3)','errcatch')
lasterror(%t)

// variable1 does not exist
if execstr('variable1;','errcatch')<>0 then disp("Trigger an error"),end

// variable2 exists ... no error is triggered by execstr
variable2=[2,3]; 
if execstr('variable2;','errcatch')<>0 then 
   disp("Trigger an error");
else
   disp("execstr is happy");
end

See Also

• evstr — evaluation of expressions
• lasterror — get last recorded error message
• error — error message
• try — beginning of try block in try-catch control instruction