| 1 | # Demonstrations for users. Could go in docs. |
| 2 | |
| 3 | #### GetValue scope and shopt --unset dynamic_scope |
| 4 | shopt --set parse_proc |
| 5 | |
| 6 | f() { |
| 7 | echo "sh x=$x" |
| 8 | } |
| 9 | |
| 10 | proc p { |
| 11 | echo "oil x=$x" |
| 12 | } |
| 13 | |
| 14 | demo() { |
| 15 | local x=dynamic |
| 16 | f |
| 17 | p |
| 18 | |
| 19 | shopt --unset dynamic_scope |
| 20 | f |
| 21 | } |
| 22 | |
| 23 | x=global |
| 24 | demo |
| 25 | echo x=$x |
| 26 | |
| 27 | ## STDOUT: |
| 28 | sh x=dynamic |
| 29 | oil x=global |
| 30 | sh x=global |
| 31 | x=global |
| 32 | ## END |
| 33 | |
| 34 | |
| 35 | #### SetValue scope and shopt --unset dynamic_scope |
| 36 | shopt --set parse_proc |
| 37 | |
| 38 | f() { |
| 39 | x=f |
| 40 | } |
| 41 | |
| 42 | proc p { |
| 43 | x=p |
| 44 | } |
| 45 | |
| 46 | demo() { |
| 47 | local x=stack |
| 48 | echo x=$x |
| 49 | echo --- |
| 50 | |
| 51 | f |
| 52 | echo f x=$x |
| 53 | |
| 54 | x=stack |
| 55 | p |
| 56 | echo p x=$x |
| 57 | |
| 58 | shopt --unset dynamic_scope |
| 59 | x=stack |
| 60 | f |
| 61 | echo funset x=$x |
| 62 | } |
| 63 | |
| 64 | x=global |
| 65 | demo |
| 66 | |
| 67 | echo --- |
| 68 | echo x=$x |
| 69 | |
| 70 | ## STDOUT: |
| 71 | x=stack |
| 72 | --- |
| 73 | f x=f |
| 74 | p x=stack |
| 75 | funset x=stack |
| 76 | --- |
| 77 | x=global |
| 78 | ## END |
| 79 | |
| 80 | #### read scope (setref) |
| 81 | set -o errexit |
| 82 | |
| 83 | read-x() { |
| 84 | echo dynamic-scope | read x |
| 85 | } |
| 86 | demo() { |
| 87 | local x=42 |
| 88 | echo x_before=$x |
| 89 | read-x |
| 90 | echo x_after=$x |
| 91 | } |
| 92 | demo |
| 93 | echo x=$x |
| 94 | |
| 95 | echo --- |
| 96 | |
| 97 | # Now 'read x' creates a local variable |
| 98 | shopt --unset dynamic_scope |
| 99 | demo |
| 100 | echo x=$x |
| 101 | |
| 102 | ## STDOUT: |
| 103 | x_before=42 |
| 104 | x_after=dynamic-scope |
| 105 | x= |
| 106 | --- |
| 107 | x_before=42 |
| 108 | x_after=42 |
| 109 | x= |
| 110 | ## END |
| 111 | |
| 112 | #### printf -v x respects dynamic_scope |
| 113 | set -o errexit |
| 114 | |
| 115 | set-x() { |
| 116 | printf -v x "%s" dynamic-scope |
| 117 | } |
| 118 | demo() { |
| 119 | local x=42 |
| 120 | echo x=$x |
| 121 | set-x |
| 122 | echo x=$x |
| 123 | } |
| 124 | demo |
| 125 | echo x=$x |
| 126 | |
| 127 | echo --- |
| 128 | |
| 129 | shopt --unset dynamic_scope # should NOT affect read |
| 130 | demo |
| 131 | echo x=$x |
| 132 | |
| 133 | ## STDOUT: |
| 134 | x=42 |
| 135 | x=dynamic-scope |
| 136 | x= |
| 137 | --- |
| 138 | x=42 |
| 139 | x=42 |
| 140 | x= |
| 141 | ## END |
| 142 | |
| 143 | #### printf -v a[i] respects dynamic_scope |
| 144 | set -o errexit |
| 145 | shopt --set eval_unsafe_arith |
| 146 | |
| 147 | set-item() { |
| 148 | printf -v 'a[1]' "%s" dynamic-scope |
| 149 | } |
| 150 | demo() { |
| 151 | local -a a=(41 42 43) |
| 152 | echo "a[1]=${a[1]}" |
| 153 | set-item |
| 154 | echo "a[1]=${a[1]}" |
| 155 | } |
| 156 | demo |
| 157 | echo "a[1]=${a[1]}" |
| 158 | |
| 159 | echo --- |
| 160 | |
| 161 | shopt --unset dynamic_scope # should NOT affect read |
| 162 | demo |
| 163 | echo "a[1]=${a[1]}" |
| 164 | |
| 165 | ## STDOUT: |
| 166 | a[1]=42 |
| 167 | a[1]=dynamic-scope |
| 168 | a[1]= |
| 169 | --- |
| 170 | a[1]=42 |
| 171 | a[1]=42 |
| 172 | a[1]= |
| 173 | ## END |
| 174 | |
| 175 | #### ${undef=a} and shopt --unset dynamic_scope |
| 176 | |
| 177 | set-x() { |
| 178 | : ${x=new} |
| 179 | } |
| 180 | demo() { |
| 181 | local x |
| 182 | echo x=$x |
| 183 | set-x |
| 184 | echo x=$x |
| 185 | } |
| 186 | |
| 187 | demo |
| 188 | echo x=$x |
| 189 | |
| 190 | echo --- |
| 191 | |
| 192 | # Now this IS affected? |
| 193 | shopt --unset dynamic_scope |
| 194 | demo |
| 195 | echo x=$x |
| 196 | ## STDOUT: |
| 197 | x= |
| 198 | x=new |
| 199 | x= |
| 200 | --- |
| 201 | x= |
| 202 | x= |
| 203 | x= |
| 204 | ## END |
| 205 | |
| 206 | #### declare -p respects it |
| 207 | __g=G |
| 208 | show-vars() { |
| 209 | local __x=X |
| 210 | declare -p | grep '__' |
| 211 | echo status=$? |
| 212 | |
| 213 | echo - |
| 214 | declare -p __y | grep '__' |
| 215 | echo status=$? |
| 216 | } |
| 217 | |
| 218 | demo() { |
| 219 | local __y=Y |
| 220 | |
| 221 | show-vars |
| 222 | echo --- |
| 223 | shopt --unset dynamic_scope |
| 224 | show-vars |
| 225 | } |
| 226 | |
| 227 | demo |
| 228 | |
| 229 | ## STDOUT: |
| 230 | declare -- __g=G |
| 231 | declare -- __x=X |
| 232 | declare -- __y=Y |
| 233 | status=0 |
| 234 | - |
| 235 | declare -- __y=Y |
| 236 | status=0 |
| 237 | --- |
| 238 | declare -- __g=G |
| 239 | declare -- __x=X |
| 240 | status=0 |
| 241 | - |
| 242 | status=1 |
| 243 | ## END |
| 244 | |
| 245 | |
| 246 | #### OshLanguageSetValue constructs |
| 247 | |
| 248 | f() { |
| 249 | (( x = 42 )) |
| 250 | } |
| 251 | demo() { |
| 252 | f |
| 253 | echo x=$x |
| 254 | } |
| 255 | |
| 256 | demo |
| 257 | |
| 258 | echo --- |
| 259 | |
| 260 | shopt --unset dynamic_scope |
| 261 | |
| 262 | unset x |
| 263 | |
| 264 | demo |
| 265 | |
| 266 | echo --- global |
| 267 | echo x=$x |
| 268 | ## STDOUT: |
| 269 | x=42 |
| 270 | --- |
| 271 | x= |
| 272 | --- global |
| 273 | x= |
| 274 | ## END |
| 275 | |
| 276 | |
| 277 | #### shell assignments 'neutered' inside 'proc' |
| 278 | shopt --set parse_proc |
| 279 | |
| 280 | # They can't mutate globals or anything higher on the stack |
| 281 | |
| 282 | proc p { |
| 283 | g=PROC |
| 284 | export e=PROC |
| 285 | } |
| 286 | |
| 287 | f() { |
| 288 | g=SH |
| 289 | export e=SH |
| 290 | } |
| 291 | |
| 292 | e=E |
| 293 | g=G |
| 294 | p |
| 295 | echo e=$e g=$g |
| 296 | |
| 297 | p |
| 298 | echo e=$e g=$g |
| 299 | |
| 300 | f |
| 301 | echo e=$e g=$g |
| 302 | |
| 303 | ## STDOUT: |
| 304 | e=E g=G |
| 305 | e=E g=G |
| 306 | e=SH g=SH |
| 307 | ## END |
| 308 | |
| 309 | #### setglobal still allows setting globals |
| 310 | shopt --set parse_proc |
| 311 | |
| 312 | proc p { |
| 313 | setglobal new_global = 'p' |
| 314 | setglobal g = 'p' |
| 315 | } |
| 316 | |
| 317 | var g = 'G' |
| 318 | |
| 319 | p |
| 320 | |
| 321 | echo g=$g new_global=$new_global |
| 322 | ## STDOUT: |
| 323 | g=p new_global=p |
| 324 | ## END |
| 325 | |
| 326 | #### setref with :out param |
| 327 | shopt --set parse_proc |
| 328 | |
| 329 | proc set-it(:s, val) { |
| 330 | #pp cell __s |
| 331 | setref s = "foo-$val" |
| 332 | } |
| 333 | |
| 334 | proc demo { |
| 335 | # TODO: Our bad implementation causes a recursion problem here because we use |
| 336 | # the name 's'. |
| 337 | if true; then |
| 338 | var s = 'abc' |
| 339 | set-it :s SS |
| 340 | echo $s |
| 341 | fi |
| 342 | |
| 343 | var t = 'def' |
| 344 | set-it :t TT |
| 345 | echo $t |
| 346 | } |
| 347 | |
| 348 | demo |
| 349 | |
| 350 | ## STDOUT: |
| 351 | foo-SS |
| 352 | foo-TT |
| 353 | ## END |
| 354 | |
| 355 | #### setref with conflicting variable name |
| 356 | shopt --set parse_proc |
| 357 | |
| 358 | proc set-it(:s, val) { |
| 359 | #pp cell __s |
| 360 | |
| 361 | # This breaks it! |
| 362 | var oops = '' |
| 363 | setref s = "foo-$val" |
| 364 | } |
| 365 | |
| 366 | proc demo { |
| 367 | var oops = '' |
| 368 | set-it :oops zz |
| 369 | echo oops=$oops |
| 370 | } |
| 371 | |
| 372 | demo |
| 373 | |
| 374 | ## STDOUT: |
| 375 | oops=foo-zz |
| 376 | ## END |
| 377 | |
| 378 | |
| 379 | #### setref of regular param is a fatal error |
| 380 | shopt --set parse_proc |
| 381 | |
| 382 | proc set-it(:s, val) { |
| 383 | setref val = 'oops' |
| 384 | } |
| 385 | |
| 386 | var s = 'abc' |
| 387 | set-it :s SS |
| 388 | echo $s |
| 389 | |
| 390 | ## status: 1 |
| 391 | ## STDOUT: |
| 392 | ## END |
| 393 | |
| 394 | #### setref equivalent without pgen2 syntax, using open proc |
| 395 | shopt --set parse_proc |
| 396 | |
| 397 | # This is kind of what we compile to. Ref params get an extra __ prefix? then |
| 398 | # that means you can't really READ them either? I think that's OK. |
| 399 | |
| 400 | # At call time, param binding time: |
| 401 | # If the PARAM has a colon prefix: |
| 402 | # Assert that the ARG has a colon prefix. Don't remove it. |
| 403 | # Set the cell.nameref flag. |
| 404 | # |
| 405 | # At Setref time: |
| 406 | # Check that it's cell.nameref. |
| 407 | # Add extra : to lvalue.{Named,Indexed,Keyed} and perform it. |
| 408 | # |
| 409 | # The __ avoids the nameref cycle check. |
| 410 | # And we probably disallow reading from the ref. That's OK. The caller can |
| 411 | # pass it in as a regular value! |
| 412 | |
| 413 | proc set-it { |
| 414 | local -n __s=$1 # nameref flag needed with setref |
| 415 | local val=$2 |
| 416 | |
| 417 | # well this part requires pgen2 |
| 418 | setref s = "foo-$val" |
| 419 | } |
| 420 | |
| 421 | var s = 'abc' |
| 422 | var t = 'def' |
| 423 | set-it s SS |
| 424 | set-it t TT # no colon here |
| 425 | echo $s |
| 426 | echo $t |
| 427 | |
| 428 | ## STDOUT: |
| 429 | foo-SS |
| 430 | foo-TT |
| 431 | ## END |
| 432 | |
| 433 | #### setref a, b = 'one', 'two' |
| 434 | shopt --set parse_proc |
| 435 | |
| 436 | proc p(x, :a, :b) { |
| 437 | setref a, b = "${x}1", "${x}2" |
| 438 | } |
| 439 | |
| 440 | p foo :c :d |
| 441 | echo c=$c d=$d |
| 442 | ## STDOUT: |
| 443 | c=foo1 d=foo2 |
| 444 | ## END |
| 445 | |
| 446 | #### setref a[i] |
| 447 | |
| 448 | # You can do this in bash/mksh. See nameref! |
| 449 | |
| 450 | proc set1(:a, item) { |
| 451 | setref a[1] = item |
| 452 | } |
| 453 | |
| 454 | var a = %(one two three) |
| 455 | var myarray = %(a b c) |
| 456 | |
| 457 | set1 :a zzz |
| 458 | set1 :myarray z |
| 459 | |
| 460 | shopt --set oil:upgrade |
| 461 | #write -- @a |
| 462 | write -- @myarray |
| 463 | |
| 464 | ## STDOUT: |
| 465 | a |
| 466 | z |
| 467 | c |
| 468 | ## END |
| 469 | |
| 470 | #### unset inside proc uses local scope |
| 471 | shopt --set parse_brace |
| 472 | shopt --set parse_proc |
| 473 | |
| 474 | f() { |
| 475 | unset x |
| 476 | } |
| 477 | |
| 478 | proc p() { |
| 479 | unset x |
| 480 | } |
| 481 | |
| 482 | proc p2() { |
| 483 | shopt --set dynamic_scope { # turn it back on |
| 484 | unset x |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | x=foo |
| 489 | f |
| 490 | echo f x=$x |
| 491 | |
| 492 | x=bar |
| 493 | p |
| 494 | echo p x=$x |
| 495 | |
| 496 | x=spam |
| 497 | p2 |
| 498 | echo p2 x=$x |
| 499 | |
| 500 | ## STDOUT: |
| 501 | f x= |
| 502 | p x=bar |
| 503 | p2 x= |
| 504 | ## END |
| 505 | |
| 506 | #### unset composes when you turn on dynamic scope |
| 507 | shopt -s oil:all |
| 508 | |
| 509 | proc unset-two { |
| 510 | shopt --set dynamic_scope { |
| 511 | unset $1 |
| 512 | unset $2 |
| 513 | } |
| 514 | } |
| 515 | |
| 516 | demo() { |
| 517 | local x=X |
| 518 | local y=Y |
| 519 | |
| 520 | echo "x=$x y=$y" |
| 521 | |
| 522 | unset-two x y |
| 523 | |
| 524 | shopt --unset nounset |
| 525 | echo "x=$x y=$y" |
| 526 | } |
| 527 | |
| 528 | demo |
| 529 | ## STDOUT: |
| 530 | x=X y=Y |
| 531 | x= y= |
| 532 | ## END |
| 533 | |
| 534 | #### Temp Bindings |
| 535 | shopt --set parse_proc |
| 536 | |
| 537 | myfunc() { |
| 538 | echo myfunc FOO=$FOO |
| 539 | } |
| 540 | proc myproc() { |
| 541 | echo myproc FOO=$FOO |
| 542 | } |
| 543 | |
| 544 | FOO=bar myfunc |
| 545 | FOO=bar myproc |
| 546 | FOO=bar echo inline FOO=$FOO |
| 547 | FOO=bar printenv.py FOO |
| 548 | |
| 549 | ## STDOUT: |
| 550 | myfunc FOO=bar |
| 551 | myproc FOO= |
| 552 | inline FOO= |
| 553 | bar |
| 554 | ## END |
| 555 | |
| 556 | #### cd blocks don't introduce new scopes |
| 557 | shopt --set oil:upgrade |
| 558 | |
| 559 | var x = 42 |
| 560 | cd / { |
| 561 | var y, z = 0, 1 |
| 562 | echo $x $y $z |
| 563 | setvar y = 43 |
| 564 | } |
| 565 | setvar z = 44 |
| 566 | echo $x $y $z |
| 567 | |
| 568 | ## STDOUT: |
| 569 | 42 0 1 |
| 570 | 42 43 44 |
| 571 | ## END |
| 572 | |
| 573 | #### IFS=: myproc exports when it doesn't need to |
| 574 | shopt --set parse_proc |
| 575 | shopt --set parse_brace |
| 576 | |
| 577 | s='xzx zxz' |
| 578 | |
| 579 | myfunc() { |
| 580 | echo myfunc IFS="$IFS" |
| 581 | argv.py $s |
| 582 | } |
| 583 | |
| 584 | proc myproc() { |
| 585 | echo myproc IFS="$IFS" |
| 586 | argv.py $s |
| 587 | } |
| 588 | |
| 589 | IFS=: $REPO_ROOT/spec/bin/printenv.py IFS |
| 590 | |
| 591 | # default value |
| 592 | echo "$IFS" | od -A n -t x1 |
| 593 | |
| 594 | IFS=' z' |
| 595 | echo IFS="$IFS" |
| 596 | |
| 597 | IFS=' x' myfunc |
| 598 | |
| 599 | # Problem: $IFS in procs only finds GLOBAL values. But when actually |
| 600 | # splitting, $IFS is a 'shvar' which respects DYNAMIC scope. |
| 601 | # - TODO: shvar_get('IFS') |
| 602 | |
| 603 | IFS=' x' myproc |
| 604 | |
| 605 | # Oil solution to the problem |
| 606 | shvar IFS=' x' { |
| 607 | myproc |
| 608 | } |
| 609 | |
| 610 | ## STDOUT: |
| 611 | : |
| 612 | 20 09 0a 0a |
| 613 | IFS= z |
| 614 | myfunc IFS= x |
| 615 | ['', 'z', 'z', 'z'] |
| 616 | myproc IFS= z |
| 617 | ['', 'z', 'z', 'z'] |
| 618 | myproc IFS= x |
| 619 | ['', 'z', 'z', 'z'] |
| 620 | ## END |
| 621 | |
| 622 | #### shvar usage |
| 623 | shopt --set oil:upgrade |
| 624 | shopt --unset errexit |
| 625 | |
| 626 | # no block |
| 627 | shvar |
| 628 | echo status=$? |
| 629 | |
| 630 | shvar { # no arg |
| 631 | true |
| 632 | } |
| 633 | echo status=$? |
| 634 | |
| 635 | shvar foo { # should be name=value |
| 636 | true |
| 637 | } |
| 638 | echo status=$? |
| 639 | ## STDOUT: |
| 640 | status=2 |
| 641 | status=2 |
| 642 | status=2 |
| 643 | ## END |
| 644 | |
| 645 | #### shvar global |
| 646 | shopt --set oil:upgrade |
| 647 | shopt --unset nounset |
| 648 | |
| 649 | echo _ESCAPER=$_ESCAPER |
| 650 | echo _DIALECT=$_DIALECT |
| 651 | |
| 652 | shvar _ESCAPER=html _DIALECT=ninja { |
| 653 | echo block _ESCAPER=$_ESCAPER |
| 654 | echo block _DIALECT=$_DIALECT |
| 655 | } |
| 656 | |
| 657 | echo _ESCAPER=$_ESCAPER |
| 658 | echo _DIALECT=$_DIALECT |
| 659 | |
| 660 | # Now set them |
| 661 | _ESCAPER=foo |
| 662 | _DIALECT=bar |
| 663 | |
| 664 | echo ___ |
| 665 | |
| 666 | echo _ESCAPER=$_ESCAPER |
| 667 | echo _DIALECT=$_DIALECT |
| 668 | |
| 669 | shvar _ESCAPER=html _DIALECT=ninja { |
| 670 | echo block _ESCAPER=$_ESCAPER |
| 671 | echo block _DIALECT=$_DIALECT |
| 672 | |
| 673 | shvar _ESCAPER=nested { |
| 674 | echo nested _ESCAPER=$_ESCAPER |
| 675 | echo nested _DIALECT=$_DIALECT |
| 676 | } |
| 677 | } |
| 678 | |
| 679 | echo _ESCAPER=$_ESCAPER |
| 680 | echo _DIALECT=$_DIALECT |
| 681 | |
| 682 | ## STDOUT: |
| 683 | _ESCAPER= |
| 684 | _DIALECT= |
| 685 | block _ESCAPER=html |
| 686 | block _DIALECT=ninja |
| 687 | _ESCAPER= |
| 688 | _DIALECT= |
| 689 | ___ |
| 690 | _ESCAPER=foo |
| 691 | _DIALECT=bar |
| 692 | block _ESCAPER=html |
| 693 | block _DIALECT=ninja |
| 694 | nested _ESCAPER=nested |
| 695 | nested _DIALECT=ninja |
| 696 | _ESCAPER=foo |
| 697 | _DIALECT=bar |
| 698 | ## END |
| 699 | |
| 700 | #### shvar local |
| 701 | shopt --set oil:upgrade # blocks |
| 702 | shopt --unset simple_word_eval # test word splitting |
| 703 | |
| 704 | proc foo { |
| 705 | shvar IFS=x MYTEMP=foo { |
| 706 | echo IFS="$IFS" |
| 707 | argv.py $s |
| 708 | echo MYTEMP=${MYTEMP:-undef} |
| 709 | } |
| 710 | } |
| 711 | var s = 'a b c' |
| 712 | argv.py $s |
| 713 | foo |
| 714 | argv.py $s |
| 715 | echo MYTEMP=${MYTEMP:-undef} |
| 716 | ## STDOUT: |
| 717 | ['a', 'b', 'c'] |
| 718 | IFS=x |
| 719 | ['a b c'] |
| 720 | MYTEMP=foo |
| 721 | ['a', 'b', 'c'] |
| 722 | MYTEMP=undef |
| 723 | ## END |
| 724 | |
| 725 | #### shvar IFS |
| 726 | shopt --set oil:upgrade |
| 727 | |
| 728 | proc myproc() { |
| 729 | echo "$IFS" | od -A n -t x1 |
| 730 | |
| 731 | local mylocal=x |
| 732 | shvar IFS=w { |
| 733 | echo inside IFS="$IFS" |
| 734 | echo mylocal="$mylocal" # I do NOT want a new scope! |
| 735 | } |
| 736 | echo "$IFS" | od -A n -t x1 |
| 737 | } |
| 738 | |
| 739 | myproc |
| 740 | ## STDOUT: |
| 741 | 20 09 0a 0a |
| 742 | inside IFS=w |
| 743 | mylocal=x |
| 744 | 20 09 0a 0a |
| 745 | ## END |
| 746 | |
| 747 | #### shvar_get() |
| 748 | shopt --set parse_proc |
| 749 | |
| 750 | s='xzx zxz' |
| 751 | |
| 752 | proc myproc { |
| 753 | echo wrong IFS="$IFS" # NOT what's used |
| 754 | echo shvar IFS=$shvar_get('IFS') # what IS used: dynamic scope |
| 755 | argv.py $s |
| 756 | } |
| 757 | |
| 758 | IFS=x |
| 759 | IFS=z myproc |
| 760 | ## STDOUT: |
| 761 | wrong IFS=x |
| 762 | shvar IFS=z |
| 763 | ['x', 'x ', 'x'] |
| 764 | ## END |