The foundation of Skips is the Block structure. A block is enclosed in { and }, and can be nested within another block. The following instructions deal with blocks.

SKIPS instructions

Equivalents

 

 

 

{ ... }

 

 

 

Defines a block (generates no code)

SKIP { ...

}

 

GOTO .S

...

*.S

 

 

SKIPL {

...

}

GOTOL .S ...

*.S

 

 

SKIPC {

...

}

GOC .S ...

*.S

 

 

SKC {

... }

 

GOC .S ...

*.S

 

 

SKIPNC

{...

}

GONC .S

...

*.S

 

 

SKNC { ...

}

 

GONC .S

...

*.S

 

 

Test SKIPYES { }...

Test GOYES .S ...

*.S

 

Test { ...

}

 

Test GOYES .S ...

*.S

 

Test

{ ...

}

 

/Test GOYES .S...

*.S

 

Test > {

... }

/Test GOYES .S ...

*.S

 

SKUB { ...

}

 

GOSUB .S ...

*.S

 

 

SKUBL {

...

}

GOSUBL .S *.S...

 

STRING

{ ...

}

$/02A2C GOIN5 *.S ...

*.S (to create a character string)

CODE { ...

}

 

$/02DCC GOIN5 *.S ...

*.S (to create a code object)

STROBJ

$PROLOG { ... }

$(5)PROLOG GOIN5 .S ... *.S (to create a ‘prolog – length’

 

 

 

 

object)

 

 

 

 

/Test is the opposite of Test. For example if Test is ?A<C.A, /Test is ?A>=C.A. The test instructions dealing with the hardware register (?HST=0, ?MP=0, ?SR=0, ?XM=0, ?SB=1, ?HST=1, ?MP=1,

?SR=1, ?XM=1 and ?SB=1) cannot be inverted.

Once blocks are defined, special instructions can be used in them. The instructions called EXIT and UP allow jumping to the end or to the beginning of a block.

These instructions

are equivalent to

{

*.Beginning

EXIT

GOTO.End

EXITC

GOC.End

EXITNC

GONC.End

?A=0.A EXIT

?A=0.A ¨.End

UP

GOTO.Beginning

UPC

GOC.Beginning

UPNC

GONC.Beginning

?A=0.A UP

?A=0.A ¨.Beginning

}

*.End

Note: In Saturn mode do not be confused between EXIT and UP instructions, which are GOTOs, and EXIT and UP after a test, which are GOYES’s. EXIT and UP can jump to the beginning or to the end of an upperle vel block by specifying the number of blocks to exit, after the UP or EXIT instructions.

The Development Library 621

Page 519
Image 519
HP 48gII Graphing, 50g Graphing manual Skips instructions Equivalents, These instructions Are equivalent to