Method and apparatus for a programming language having fully undoable, timed reactive instructions

A method of executing an undoable program, comprising:

• saving a then existing global program state to a memory at each of a plurality of predetermined points in the executing program;
• receiving an instruction to return program execution to a previous one of said plurality of predetermined points;
• saving a return global program state in response to the instruction to return;
• recovering the saved global program state associated with said previous one predetermined point;
• and
• continuing executing the program from said saved global program state associated with said previous one predetermined point.

A machine-readable medium having stored thereon program instructions to enable an executing program to fully recovery to a previous program state, the instructions, if executed, configure a processor to:

• save a then existing global program state to a memory at each of a plurality of predetermined points in the executing program;
• receive an instruction to return program execution to a previous one of said plurality of predetermined points;
• save a return global program state in response to the instruction to return;
• recover the saved global program state associated with said previous one predetermined point;
• and
• continue executing the program from said saved global program state associated with said previous one predetermined point.

A method of executing an undoable program comprising:

• saving a plurality of global program states at a plurality of predetermined points in the executing program;
• receiving a first instruction to return to a last saved global program state;
• receiving a second request to return to a last saved global program state within a predetermined timeout period of said first instruction;
• saving a first redo global program state in response to the second request to return;
• recovering a next to last saved global program state;
• and
• continuing executing the program from the recovered next to last saved global program state.

A processing system comprising:

• a processor;
• a memory coupled to the processor;
• an executable program stored in the memory, the executable program Including instructions to enable an executing program to fully recovery to a previous program state, the instructions, if executed, configure a processor to:
• save a first global program state at a predetermined point in the executing program;
• receive an instruction to return to said first saved global program state;
• save a second global program state in response to the instruction to return;
• recover the first saved global program state;
• and
• continue executing the program from said first saved global program state.