1	# Demonstrations for users. Could go in docs.
2
3	#### GetValue scope and shopt --unset dynamic_scope
4
5	f() {
6	echo "sh x=$x"
7	}
8
9	proc p {
10	echo "oil x=$x"
11	}
12
13	demo() {
14	local x=dynamic
15	f
16	p
17
18	shopt --unset dynamic_scope
19	f
20	}
21
22	x=global
23	demo
24	echo x=$x
25
26	## STDOUT:
27	sh x=dynamic
28	oil x=global
29	sh x=global
30	x=global
31	## END
32
33
34	#### SetValue scope and shopt --unset dynamic_scope
35	f() {
36	x=f
37	}
38
39	proc p {
40	x=p
41	}
42
43	demo() {
44	local x=stack
45	echo x=$x
46	echo ---
47
48	f
49	echo f x=$x
50
51	x=stack
52	p
53	echo p x=$x
54
55	shopt --unset dynamic_scope
56	x=stack
57	f
58	echo funset x=$x
59	}
60
61	x=global
62	demo
63
64	echo ---
65	echo x=$x
66
67	## STDOUT:
68	x=stack
69	---
70	f x=f
71	p x=stack
72	funset x=stack
73	---
74	x=global
75	## END
76
77	#### read scope (setref)
78	read-x() {
79	echo new | read x
80	}
81	demo() {
82	local x=42
83	echo x=$x
84	read-x
85	echo x=$x
86	}
87	demo
88	echo x=$x
89
90	echo ---
91
92	shopt --unset dynamic_scope # should NOT affect read
93	demo
94	echo x=$x
95
96	## STDOUT:
97	x=42
98	x=new
99	x=
100	---
101	x=42
102	x=new
103	x=
104	## END
105
106	#### printf -v scope (setref)
107	set-x() {
108	printf -v x "%s" new
109	}
110	demo() {
111	local x=42
112	echo x=$x
113	set-x
114	echo x=$x
115	}
116	demo
117	echo x=$x
118
119	echo ---
120
121	shopt --unset dynamic_scope # should NOT affect read
122	demo
123	echo x=$x
124
125	## STDOUT:
126	x=42
127	x=new
128	x=
129	---
130	x=42
131	x=new
132	x=
133	## END
134
135	#### ${undef=a} and shopt --unset dynamic_scope
136
137	set-x() {
138	: ${x=new}
139	}
140	demo() {
141	local x
142	echo x=$x
143	set-x
144	echo x=$x
145	}
146
147	demo
148	echo x=$x
149
150	echo ---
151
152	# Now this IS affected?
153	shopt --unset dynamic_scope
154	demo
155	echo x=$x
156	## STDOUT:
157	x=
158	x=new
159	x=
160	---
161	x=
162	x=
163	x=
164	## END
165
166	#### declare -p respects it
167	__g=G
168	show-vars() {
169	local __x=X
170	declare -p | grep '__'
171	echo status=$?
172
173	echo -
174	declare -p __y | grep '__'
175	echo status=$?
176	}
177
178	demo() {
179	local __y=Y
180
181	show-vars
182	echo ---
183	shopt --unset dynamic_scope
184	show-vars
185	}
186
187	demo
188
189	## STDOUT:
190	declare -- __g=G
191	declare -- __x=X
192	declare -- __y=Y
193	status=0
194	-
195	declare -- __y=Y
196	status=0
197	---
198	declare -- __g=G
199	declare -- __x=X
200	status=0
201	-
202	status=1
203	## END
204
205
206
207	#### unset composes because it uses dynamic scope (even in Oil)
208	shopt -s oil:all
209
210	proc unset-two {
211	unset $1
212	unset $2
213	}
214
215	demo() {
216	local x=X
217	local y=Y
218
219	echo "x=$x y=$y"
220
221	unset-two x y
222
223	shopt --unset nounset
224	echo "x=$x y=$y"
225	}
226
227	demo
228	## STDOUT:
229	x=X y=Y
230	x= y=
231	## END
232
233
234	#### SetLocalShopt constructs
235
236	f() {
237	(( x = 42 ))
238	}
239	demo() {
240	f
241	echo x=$x
242	}
243
244	demo
245
246	echo ---
247
248	shopt --unset dynamic_scope
249
250	unset x
251
252	demo
253
254	echo --- global
255	echo x=$x
256	## STDOUT:
257	x=42
258	---
259	x=
260	--- global
261	x=
262	## END
263
264
265	#### shell assignments 'neutered' inside 'proc'
266
267	# They can't mutate globals or anything higher on the stack
268
269	proc p {
270	g=PROC
271	export e=PROC
272	}
273
274	f() {
275	g=SH
276	export e=SH
277	}
278
279	e=E
280	g=G
281	p
282	echo e=$e g=$g
283
284	p
285	echo e=$e g=$g
286
287	f
288	echo e=$e g=$g
289
290	## STDOUT:
291	e=E g=G
292	e=E g=G
293	e=SH g=SH
294	## END
295
296	#### setvar still allows setting globals
297
298	proc p {
299	setvar new_global = 'p'
300	setvar g = 'p'
301	}
302
303	var g = 'G'
304
305	p
306
307	echo g=$g new_global=$new_global
308	## STDOUT:
309	g=p new_global=p
310	## END
311
312	#### setref with :out param
313
314	# The name is mangled with : so you can't use it
315	proc append(:s, suffix) {
316	setref s = "$s-$suffix"
317	}
318
319	proc set-it(:s, val) {
320	#pp cell __s
321	setref s = "foo-$val"
322	}
323
324	proc demo {
325	var s = 'abc'
326	var t = 'def'
327	set-it :s SS
328	set-it :t TT
329
330	echo $s
331	echo $t
332	}
333
334	demo
335
336	## STDOUT:
337	foo-SS
338	foo-TT
339	## END
340
341	#### setref without :out param
342	proc set-it(:s, val) {
343	setref val = 'oops'
344	}
345
346	var s = 'abc'
347	set-it :s SS
348	echo $s
349
350	## status: 1
351	## STDOUT:
352	## END
353
354	#### setref: syntax without pgen2 using open proc
355
356	# This is kind of what we compile to. Ref params get an extra __ prefix? then
357	# that means you can't really READ them either? I think that's OK.
358
359	# At call time, param binding time:
360	# If the PARAM has a colon prefix:
361	# Assert that the ARG has a colon prefix. Don't remove it.
362	# Set the cell.nameref flag.
363	#
364	# At Setref time:
365	# Check that it's cell.nameref.
366	# Add extra : to lvalue.{Named,Indexed,Keyed} and perform it.
367	#
368	# The __ avoids the nameref cycle check.
369	# And we probably disallow reading from the ref. That's OK. The caller can
370	# pass it in as a regular value!
371
372	proc set-it {
373	local -n __s=$1 # nameref flag needed with setref
374	local val=$2
375
376	# well this part requires pgen2
377	setref s = "foo-$val"
378	}
379
380	var s = 'abc'
381	var t = 'def'
382	set-it s SS
383	set-it t TT # no colon here
384	echo $s
385	echo $t
386
387	## STDOUT:
388	foo-SS
389	foo-TT
390	## END
391
392	#### setref a[i]
393
394	# You can do this in bash/mksh. See nameref!
395
396	proc set1(:a, item) {
397	setref a[1] = item
398	}
399
400	var a = %(one two three)
401	var myarray = %(a b c)
402
403	set1 :a zzz
404	set1 :myarray z
405
406	shopt --set oil:basic
407	#write -- @a
408	write -- @myarray
409
410	## STDOUT:
411	a
412	z
413	c
414	## END