3 Jul 2012
Today I was writing some code for handling interrupts. At one point I needed the following piece of code
extern void isr0(void), isr1(void), isr2(void), isr3(void), isr4(void), isr5(void), isr6(void), isr7(void), isr8(void), isr9(void), isr10(void), isr11(void), isr12(void), isr13(void), isr14(void), isr15(void), isr16(void), isr17(void), isr18(void), isr19(void), isr20(void), isr21(void), isr22(void), isr23(void), isr24(void), isr25(void), isr26(void), isr27(void), isr28(void), isr29(void), isr30(void), isr31(void), isr32(void), isr33(void), isr34(void), isr35(void), isr36(void), isr37(void), isr38(void), isr39(void), isr40(void), isr41(void), isr42(void), isr43(void), isr44(void), isr45(void), isr46(void), isr47(void);
Vim macros.
I've been using this site and my rewrite of my operating system as an excuse to learn vim. And today it payed off. To write the above piece of code I used the key presses
iisr0(void),<esc>0qayyp3l<ctrl>a0q46@a47k48J$r;Iextern void <esc>
Couldn't be easier!
OK, so maybe it could... Let's break it down.
Let's start with
iisr0(void),<esc>
i puts vim in Insert mode. There we write isr0(void), and finally leave Insert mode with the escape key.
Next is 0 to bring the pointer to the beginning of the line. Then comes the macro.
qayyp3l<ctrl>a0q
qa starts recording a macro into register a.
yyp yanks the current line and pastes it below.
3l skips over the i, s and r.
Ctrl+a increases the number under the pointer by one.
Finally 0 goes back to the beginning of the line and q stops the macro recording.
The next part:
46@a47k48J
runs the macro 46 times, steps up 47 times and joins the current line with the next 48 times. We now have
isr0(void), isr1(void), isr2(void), isr3(void), isr4(void), isr5(void), isr6(void), isr7(void), isr8(void), isr9(void), isr10(void), isr11(void), isr12(void), isr13(void), isr14(void), isr15(void), isr16(void), isr17(void), isr18(void), isr19(void), isr20(void), isr21(void), isr22(void), isr23(void), isr24(void), isr25(void), isr26(void), isr27(void), isr28(void), isr29(void), isr30(void), isr31(void), isr32(void), isr33(void), isr34(void), isr35(void), isr36(void), isr37(void), isr38(void), isr39(void), isr40(void), isr41(void), isr42(void), isr43(void), isr44(void), isr45(void), isr46(void),
and all we need to do now is replace the last comma with a semicolon using $r; and insert extern void at the beginning of the line using I.
Starting with
INTNOERR 0
I used
qayypcwINTNOERR<esc>$<ctrl>a0q qsyypcwINTERR<esc>$<ctrl>a0q dd6@a@s@a5@s33@a
and ended up with
INTNOERR 0 INTNOERR 1 INTNOERR 2 INTNOERR 3 INTNOERR 4 INTNOERR 5 INTNOERR 6 INTNOERR 7 INTERR 8 INTNOERR 9 INTERR 10 INTERR 11 INTERR 12 INTERR 13 INTERR 14 INTNOERR 15 ... INTNOERR 45 INTNOERR 46
I love vim!
So where did I use this? I've been writing some code for handling interrupts in the os. You can find it in Git commit 26dd8e4c75.