STRING REGISTER

1. AR is an Argument Register, which means it takes a value that you pass to it at declaration. Example, you can call a program SQUARE(2,3) and then SQUARE will read something along the lines of R[AR[1]] = AR[2] * AR[2], which will then place the value of 3 squared into register 2.

2. Yes, you can use any string, within limits, in a string register. There will be some characters that i am sure you cannot make, and length limitations, but otherwise, a string is a string.

Fun fact about the String Registers, you can add them together and use them to indirectly call programs or vision processes.

SR[1] = 'ANY'

SR[2] = ' STRING'

SR[3] = SR[1] + SR[2]

Now SR[3] = 'ANY STRING'

I use them a lot for choosing vision processes when my system has several different parts it needs to check or move.

Program:

CALL MAKE_STR('ANY',' STRING')

Program MAKE_STR:

SR[1]=AR[1]+AR[2]

Regarding manipulating SRs in TP (not KAREL), the trick of calling a subroutine with strings as arguments seen in Post #4 above works for me, but the direct assignment shown in Post #3 doesn't. So,

CALL MAKE_STR ('Any', 'String') works

SR[1] = AR[1] + AR[2] inside MAKE_STR works

SR[1] = SR[2] + SR[3] works

SR[1] = 'Any string' will not build in RoboGuide (I'm writing .LS files and compiling them to .TP).

Is there a trick to doing this, or am I just running into an inherent limitation of TP language?

Nope, setting a string directly is not allowed in TP. You have to call a 'setting' program like the make_str defined above.

I think post #3 was just defining what was in the string registers.