[unix-history] / usr / lib / learn / editor / L54.1b

#print
The fact that the system remembers the last regular expression
it had is particularly useful when the regular expression is
complex.  Suppose, for example, you know that the
words "first" and "second" appear on the same line and you wish
to delete them and everything between them.  You could write
  /first.*second/s/first.*second//p
but isn't it easier to do
  /first.*second/s///p
Edit the file "passage"; the words "twentieth" and "impending" appear
on the same line.  Replace them and everything between
them by the word "impending" (i.e. delete from "twentieth"
up to but not including "impending").  One command, if you can.
Then rewrite the file and type ready.
#create Ref
   America's rise to world power is a consequence of the nation's
geographic position, natural resources, and dynamic energy.  For
the first century and more of national history, however, continental
expansion and internal developments largely absorbed the energies
of the American people.  Every dictate of public interest emphasized
the importance of avoiding all entanglements that might involve the
young republic in foreign rivalries and foreign wars.  Only with the
impending shifts
in the European balance of power, and the growth of American economic
and industrial strength create a situation that made impossible a
continued aloofness from international affairs.
#create passage
   America's rise to world power is a consequence of the nation's
geographic position, natural resources, and dynamic energy.  For
the first century and more of national history, however, continental
expansion and internal developments largely absorbed the energies
of the American people.  Every dictate of public interest emphasized
the importance of avoiding all entanglements that might involve the
young republic in foreign rivalries and foreign wars.  Only with the
twentieth century did a rapidly contracting world, impending shifts
in the European balance of power, and the growth of American economic
and industrial strength create a situation that made impossible a
continued aloofness from international affairs.
#user
#cmp passage Ref
#log
#next
55.1a 10
Commit	Line	Data
3eb5d546 C	1	#print
	2	The fact that the system remembers the last regular expression
	3	it had is particularly useful when the regular expression is
	4	complex. Suppose, for example, you know that the
	5	words "first" and "second" appear on the same line and you wish
	6	to delete them and everything between them. You could write
	7	/first.second/s/first.second//p
	8	but isn't it easier to do
	9	/first.*second/s///p
	10	Edit the file "passage"; the words "twentieth" and "impending" appear
	11	on the same line. Replace them and everything between
	12	them by the word "impending" (i.e. delete from "twentieth"
	13	up to but not including "impending"). One command, if you can.
	14	Then rewrite the file and type ready.
	15	#create Ref
	16	America's rise to world power is a consequence of the nation's
	17	geographic position, natural resources, and dynamic energy. For
	18	the first century and more of national history, however, continental
	19	expansion and internal developments largely absorbed the energies
	20	of the American people. Every dictate of public interest emphasized
	21	the importance of avoiding all entanglements that might involve the
	22	young republic in foreign rivalries and foreign wars. Only with the
	23	impending shifts
	24	in the European balance of power, and the growth of American economic
	25	and industrial strength create a situation that made impossible a
	26	continued aloofness from international affairs.
	27	#create passage
	28	America's rise to world power is a consequence of the nation's
	29	geographic position, natural resources, and dynamic energy. For
	30	the first century and more of national history, however, continental
	31	expansion and internal developments largely absorbed the energies
	32	of the American people. Every dictate of public interest emphasized
	33	the importance of avoiding all entanglements that might involve the
	34	young republic in foreign rivalries and foreign wars. Only with the
	35	twentieth century did a rapidly contracting world, impending shifts
	36	in the European balance of power, and the growth of American economic
	37	and industrial strength create a situation that made impossible a
	38	continued aloofness from international affairs.
	39	#user
	40	#cmp passage Ref
	41	#log
	42	#next
	43	55.1a 10