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#!/bin/sh
# Translate SubX by running the self-hosted translator in emulated mode on
# Linux or BSD or Mac.
#
# Possible knobs:
#   Whether to run a phase natively or in emulated mode.
#     Just always emulate for now since we debug on non-Linux.
#   Whether to stop after a phase.
#     Just always run all phases, but print out phases so it's clear where an
#     error happens.
#   Whether to trace a phase. Whether to always trace or rerun with tracing
#   enabled after an error.
#     Leave tracing to other scripts. We save intermediate files so it's easy
#     to rerun a single phase afterwards.
#   Whether to run a phase with debug information. (Need to juggle multiple
#   sets of debug files.)
#     Again, that's for subsequent scripts.

set -e

./build

cat $*          |./bootstrap_bin run apps/braces   > a.braces
cat a.braces    |./bootstrap_bin run apps/calls    > a.calls
cat a.calls     |./bootstrap_bin run apps/sigils   > a.sigils
cat a.sigils    |./bootstrap_bin run apps/tests    > a.tests
cat a.tests     |./bootstrap_bin run apps/dquotes  > a.dquotes
cat a.dquotes   |./bootstrap_bin run apps/assort   > a.assort
cat a.assort    |./bootstrap_bin run apps/pack     > a.pack
cat a.pack      |./bootstrap_bin run apps/survey   > a.survey
cat a.survey    |./bootstrap_bin run apps/hex      > a.elf

chmod +x a.elf
#n664'>664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427
# Some useful helpers for dealing with text (arrays of characters)

def equal a:text, b:text -> result:bool [
  local-scope
  load-inputs
  an:num, bn:num <- deaddress a, b
  address-equal?:boolean <- equal an, bn
  return-if address-equal?, true
  return-unless a, false
  return-unless b, false
  a-len:num <- length *a
  b-len:num <- length *b
  # compare lengths
  trace 99, [text-equal], [comparing lengths]
  length-equal?:bool <- equal a-len, b-len
  return-unless length-equal?, false
  # compare each corresponding character
  trace 99, [text-equal], [comparing characters]
  i:num <- copy 0
  {
    done?:bool <- greater-or-equal i, a-len
    break-if done?
    a2:char <- index *a, i
    b2:char <- index *b, i
    chars-match?:bool <- equal a2, b2
    return-unless chars-match?, false
    i <- add i, 1
    loop
  }
  return true
]

scenario text-equal-reflexive [
  local-scope
  x:text <- new [abc]
  run [
    10:bool/raw <- equal x, x
  ]
  memory-should-contain [
    10 <- 1  # x == x for all x
  ]
]

scenario text-equal-identical [
  local-scope
  x:text <- new [abc]
  y:text <- new [abc]
  run [
    10:bool/raw <- equal x, y
  ]
  memory-should-contain [
    10 <- 1  # abc == abc
  ]
]

scenario text-equal-distinct-lengths [
  local-scope
  x:text <- new [abc]
  y:text <- new [abcd]
  run [
    10:bool/raw <- equal x, y
  ]
  memory-should-contain [
    10 <- 0  # abc != abcd
  ]
  trace-should-contain [
    text-equal: comparing lengths
  ]
  trace-should-not-contain [
    text-equal: comparing characters
  ]
]

scenario text-equal-with-empty [
  local-scope
  x:text <- new []
  y:text <- new [abcd]
  run [
    10:bool/raw <- equal x, y
  ]
  memory-should-contain [
    10 <- 0  # "" != abcd
  ]
]

scenario text-equal-with-null [
  local-scope
  x:text <- new [abcd]
  y:text <- copy null
  run [
    10:bool/raw <- equal x, null
    11:bool/raw <- equal null, x
    12:bool/raw <- equal x, y
    13:bool/raw <- equal y, x
    14:bool/raw <- equal y, y
  ]
  memory-should-contain [
    10 <- 0
    11 <- 0
    12 <- 0
    13 <- 0
    14 <- 1
  ]
  check-trace-count-for-label 0, [error]
]

scenario text-equal-common-lengths-but-distinct [
  local-scope
  x:text <- new [abc]
  y:text <- new [abd]
  run [
    10:bool/raw <- equal x, y
  ]
  memory-should-contain [
    10 <- 0  # abc != abd
  ]
]

# A new type to help incrementally construct texts.
container buffer:_elem [
  length:num
  data:&:@:_elem
]

def new-buffer capacity:num -> result:&:buffer:_elem [
  local-scope
  load-inputs
  result <- new {(buffer _elem): type}
  *result <- put *result, length:offset, 0
  {
    break-if capacity
    # capacity not provided
    capacity <- copy 10
  }
  data:&:@:_elem <- new _elem:type, capacity
  *result <- put *result, data:offset, data
  return result
]

def grow-buffer buf:&:buffer:_elem -> buf:&:buffer:_elem [
  local-scope
  load-inputs
  # double buffer size
  olddata:&:@:_elem <- get *buf, data:offset
  oldlen:num <- length *olddata
  newlen:num <- multiply oldlen, 2
  newdata:&:@:_elem <- new _elem:type, newlen
  *buf <- put *buf, data:offset, newdata
  # copy old contents
  i:num <- copy 0
  {
    done?:bool <- greater-or-equal i, oldlen
    break-if done?
    src:_elem <- index *olddata, i
    *newdata <- put-index *newdata, i, src
    i <- add i, 1
    loop
  }
]

def buffer-full? in:&:buffer:_elem -> result:bool [
  local-scope
  load-inputs
  len:num <- get *in, length:offset
  s:&:@:_elem <- get *in, data:offset
  capacity:num <- length *s
  result <- greater-or-equal len, capacity
]

# most broadly applicable definition of append to a buffer
def append buf:&:buffer:_elem, x:_elem -> buf:&:buffer:_elem [
  local-scope
  load-inputs
  len:num <- get *buf, length:offset
  {
    # grow buffer if necessary
    full?:bool <- buffer-full? buf
    break-unless full?
    buf <- grow-buffer buf
  }
  s:&:@:_elem <- get *buf, data:offset
  *s <- put-index *s, len, x
  len <- add len, 1
  *buf <- put *buf, length:offset, len
]

# most broadly applicable definition of append to a buffer of characters: just
# call to-text
def append buf:&:buffer:char, x:_elem -> buf:&:buffer:char [
  local-scope
  load-inputs
  text:text <- to-text x
  buf <- append buf, text
]

# specialization for characters that is backspace-aware
def append buf:&:buffer:char, c:char -> buf:&:buffer:char [
  local-scope
  load-inputs
  len:num <- get *buf, length:offset
  {
    # backspace? just drop last character if it exists and return
    backspace?:bool <- equal c, 8/backspace
    break-unless backspace?
    empty?:bool <- lesser-or-equal len, 0
    return-if empty?
    len <- subtract len, 1
    *buf <- put *buf, length:offset, len
    return
  }
  {
    # grow buffer if necessary
    full?:bool <- buffer-full? buf
    break-unless full?
    buf <- grow-buffer buf
  }
  s:text <- get *buf, data:offset
  *s <- put-index *s, len, c
  len <- add len, 1
  *buf <- put *buf, length:offset, len
]

def append buf:&:buffer:_elem, t:&:@:_elem -> buf:&:buffer:_elem [
  local-scope
  load-inputs
  len:num <- length *t
  i:num <- copy 0
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    x:_elem <- index *t, i
    buf <- append buf, x
    i <- add i, 1
    loop
  }
]

scenario append-to-empty-buffer [
  local-scope
  x:&:buffer:char <- new-buffer
  run [
    c:char <- copy 97/a
    x <- append x, c
    10:num/raw <- get *x, length:offset
    s:text <- get *x, data:offset
    11:char/raw <- index *s, 0
    12:char/raw <- index *s, 1
  ]
  memory-should-contain [
    10 <- 1  # buffer length
    11 <- 97  # a
    12 <- 0  # rest of buffer is empty
  ]
]

scenario append-to-buffer [
  local-scope
  x:&:buffer:char <- new-buffer
  c:char <- copy 97/a
  x <- append x, c
  run [
    c <- copy 98/b
    x <- append x, c
    10:num/raw <- get *x, length:offset
    s:text <- get *x, data:offset
    11:char/raw <- index *s, 0
    12:char/raw <- index *s, 1
    13:char/raw <- index *s, 2
  ]
  memory-should-contain [
    10 <- 2  # buffer length
    11 <- 97  # a
    12 <- 98  # b
    13 <- 0  # rest of buffer is empty
  ]
]

scenario append-grows-buffer [
  local-scope
  x:&:buffer:char <- new-buffer 3
  s1:text <- get *x, data:offset
  x <- append x, [abc]  # buffer is now full
  s2:text <- get *x, data:offset
  run [
    10:bool/raw <- equal s1, s2
    11:@:char/raw <- copy *s2
    +buffer-filled
    c:char <- copy 100/d
    x <- append x, c
    s3:text <- get *x, data:offset
    20:bool/raw <- equal s1, s3
    21:num/raw <- get *x, length:offset
    30:@:char/raw <- copy *s3
  ]
  memory-should-contain [
    # before +buffer-filled
    10 <- 1   # no change in data pointer after original append
    11 <- 3   # size of data
    12 <- 97  # data
    13 <- 98
    14 <- 99
    # in the end
    20 <- 0   # data pointer has grown after second append
    21 <- 4   # final length
    30 <- 6   # but data's capacity has doubled
    31 <- 97  # data
    32 <- 98
    33 <- 99
    34 <- 100
    35 <- 0
    36 <- 0
  ]
]

scenario buffer-append-handles-backspace [
  local-scope
  x:&:buffer:char <- new-buffer
  x <- append x, [ab]
  run [
    c:char <- copy 8/backspace
    x <- append x, c
    s:text <- buffer-to-array x
    10:@:char/raw <- copy *s
  ]
  memory-should-contain [
    10 <- 1   # length
    11 <- 97  # contents
    12 <- 0
  ]
]

scenario append-to-buffer-of-non-characters [
  local-scope
  x:&:buffer:text <- new-buffer 1/capacity
  # no errors
]

def buffer-to-array in:&:buffer:_elem -> result:&:@:_elem [
  local-scope
  load-inputs
  # propagate null buffer
  return-unless in, null
  len:num <- get *in, length:offset
  s:&:@:_elem <- get *in, data:offset
  # we can't just return s because it is usually the wrong length
  result <- new _elem:type, len
  i:num <- copy 0
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    src:_elem <- index *s, i
    *result <- put-index *result, i, src
    i <- add i, 1
    loop
  }
]

def blank? x:&:@:_elem -> result:bool [
  local-scope
  load-inputs
  return-unless x, true
  len:num <- length *x
  result <- equal len, 0
]

# Append any number of texts together.
# A later layer also translates calls to this to implicitly call to-text, so
# append to string becomes effectively dynamically typed.
#
# Beware though: this hack restricts how much 'append' can be overridden. Any
# new variants that match:
#   append _:text, ___
# will never ever get used.
def append first:text -> result:text [
  local-scope
  load-inputs
  buf:&:buffer:char <- new-buffer 30
  # append first input
  {
    break-unless first
    buf <- append buf, first
  }
  # append remaining inputs
  {
    arg:text, arg-found?:bool <- next-input
    break-unless arg-found?
    loop-unless arg
    buf <- append buf, arg
    loop
  }
  result <- buffer-to-array buf
]

scenario text-append-1 [
  local-scope
  x:text <- new [hello,]
  y:text <- new [ world!]
  run [
    z:text <- append x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [hello, world!]
  ]
]

scenario text-append-null [
  local-scope
  x:text <- copy null
  y:text <- new [ world!]
  run [
    z:text <- append x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [ world!]
  ]
]

scenario text-append-null-2 [
  local-scope
  x:text <- new [hello,]
  y:text <- copy null
  run [
    z:text <- append x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [hello,]
  ]
]

scenario text-append-multiary [
  local-scope
  x:text <- new [hello, ]
  y:text <- new [world]
  z:text <- new [!]
  run [
    z:text <- append x, y, z
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [hello, world!]
  ]
]

scenario replace-character-in-text [
  local-scope
  x:text <- new [abc]
  run [
    x <- replace x, 98/b, 122/z
    10:@:char/raw <- copy *x
  ]
  memory-should-contain [
    10:array:character <- [azc]
  ]
]

def replace s:text, oldc:char, newc:char, from:num/optional -> s:text [
  local-scope
  load-inputs
  len:num <- length *s
  i:num <- find-next s, oldc, from
  done?:bool <- greater-or-equal i, len
  return-if done?
  *s <- put-index *s, i, newc
  i <- add i, 1
  s <- replace s, oldc, newc, i
]

scenario replace-character-at-start [
  local-scope
  x:text <- new [abc]
  run [
    x <- replace x, 97/a, 122/z
    10:@:char/raw <- copy *x
  ]
  memory-should-contain [
    10:array:character <- [zbc]
  ]
]

scenario replace-character-at-end [
  local-scope
  x:text <- new [abc]
  run [
    x <- replace x, 99/c, 122/z
    10:@:char/raw <- copy *x
  ]
  memory-should-contain [
    10:array:character <- [abz]
  ]
]

scenario replace-character-missing [
  local-scope
  x:text <- new [abc]
  run [
    x <- replace x, 100/d, 122/z
    10:@:char/raw <- copy *x
  ]
  memory-should-contain [
    10:array:character <- [abc]
  ]
]

scenario replace-all-characters [
  local-scope
  x:text <- new [banana]
  run [
    x <- replace x, 97/a, 122/z
    10:@:char/raw <- copy *x
  ]
  memory-should-contain [
    10:array:character <- [bznznz]
  ]
]

# replace underscores in first with remaining args
def interpolate template:text -> result:text [
  local-scope
  load-inputs  # consume just the template
  # compute result-len, space to allocate for result
  tem-len:num <- length *template
  result-len:num <- copy tem-len
  {
    # while inputs remain
    a:text, arg-received?:bool <- next-input
    break-unless arg-received?
    # result-len = result-len + arg.length - 1 (for the 'underscore' being replaced)
    a-len:num <- length *a
    result-len <- add result-len, a-len
    result-len <- subtract result-len, 1
    loop
  }
  rewind-inputs
  _ <- next-input  # skip template
  result <- new character:type, result-len
  # repeatedly copy sections of template and 'holes' into result
  result-idx:num <- copy 0
  i:num <- copy 0
  {
    # while arg received
    a:text, arg-received?:bool <- next-input
    break-unless arg-received?
    # copy template into result until '_'
    {
      # while i < template.length
      tem-done?:bool <- greater-or-equal i, tem-len
      break-if tem-done?, +done
      # while template[i] != '_'
      in:char <- index *template, i
      underscore?:bool <- equal in, 95/_
      break-if underscore?
      # result[result-idx] = template[i]
      *result <- put-index *result, result-idx, in
      i <- add i, 1
      result-idx <- add result-idx, 1
      loop
    }
    # copy 'a' into result
    j:num <- copy 0
    {
      # while j < a.length
      arg-done?:bool <- greater-or-equal j, a-len
      break-if arg-done?
      # result[result-idx] = a[j]
      in:char <- index *a, j
      *result <- put-index *result, result-idx, in
      j <- add j, 1
      result-idx <- add result-idx, 1
      loop
    }
    # skip '_' in template
    i <- add i, 1
    loop  # interpolate next arg
  }
  +done
  # done with holes; copy rest of template directly into result
  {
    # while i < template.length
    tem-done?:bool <- greater-or-equal i, tem-len
    break-if tem-done?
    # result[result-idx] = template[i]
    in:char <- index *template, i
    *result <- put-index *result, result-idx, in
    i <- add i, 1
    result-idx <- add result-idx, 1
    loop
  }
]

scenario interpolate-works [
  local-scope
  x:text <- new [abc_ghi]
  y:text <- new [def]
  run [
    z:text <- interpolate x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [abcdefghi]
  ]
]

scenario interpolate-at-start [
  local-scope
  x:text <- new [_, hello!]
  y:text <- new [abc]
  run [
    z:text <- interpolate x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [abc, hello!]
    22 <- 0  # out of bounds
  ]
]

scenario interpolate-at-end [
  local-scope
  x:text <- new [hello, _]
  y:text <- new [abc]
  run [
    z:text <- interpolate x, y
    10:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [hello, abc]
  ]
]

# result:bool <- space? c:char
def space? c:char -> result:bool [
  local-scope
  load-inputs
  # most common case first
  result <- equal c, 32/space
  return-if result
  result <- equal c, 10/newline
  return-if result
  result <- equal c, 9/tab
  return-if result
  result <- equal c, 13/carriage-return
  return-if result
  # remaining uncommon cases in sorted order
  # http://unicode.org code-points in unicode-set Z and Pattern_White_Space
  result <- equal c, 11/ctrl-k
  return-if result
  result <- equal c, 12/ctrl-l
  return-if result
  result <- equal c, 133/ctrl-0085
  return-if result
  result <- equal c, 160/no-break-space
  return-if result
  result <- equal c, 5760/ogham-space-mark
  return-if result
  result <- equal c, 8192/en-quad
  return-if result
  result <- equal c, 8193/em-quad
  return-if result
  result <- equal c, 8194/en-space
  return-if result
  result <- equal c, 8195/em-space
  return-if result
  result <- equal c, 8196/three-per-em-space
  return-if result
  result <- equal c, 8197/four-per-em-space
  return-if result
  result <- equal c, 8198/six-per-em-space
  return-if result
  result <- equal c, 8199/figure-space
  return-if result
  result <- equal c, 8200/punctuation-space
  return-if result
  result <- equal c, 8201/thin-space
  return-if result
  result <- equal c, 8202/hair-space
  return-if result
  result <- equal c, 8206/left-to-right
  return-if result
  result <- equal c, 8207/right-to-left
  return-if result
  result <- equal c, 8232/line-separator
  return-if result
  result <- equal c, 8233/paragraph-separator
  return-if result
  result <- equal c, 8239/narrow-no-break-space
  return-if result
  result <- equal c, 8287/medium-mathematical-space
  return-if result
  result <- equal c, 12288/ideographic-space
]

def trim s:text -> result:text [
  local-scope
  load-inputs
  len:num <- length *s
  # left trim: compute start
  start:num <- copy 0
  {
    {
      at-end?:bool <- greater-or-equal start, len
      break-unless at-end?
      result <- new character:type, 0
      return
    }
    curr:char <- index *s, start
    whitespace?:bool <- space? curr
    break-unless whitespace?
    start <- add start, 1
    loop
  }
  # right trim: compute end
  end:num <- subtract len, 1
  {
    not-at-start?:bool <- greater-than end, start
    assert not-at-start?, [end ran up against start]
    curr:char <- index *s, end
    whitespace?:bool <- space? curr
    break-unless whitespace?
    end <- subtract end, 1
    loop
  }
  # result = new character[end+1 - start]
  new-len:num <- subtract end, start, -1
  result:text <- new character:type, new-len
  # copy the untrimmed parts between start and end
  i:num <- copy start
  j:num <- copy 0
  {
    # while i <= end
    done?:bool <- greater-than i, end
    break-if done?
    # result[j] = s[i]
    src:char <- index *s, i
    *result <- put-index *result, j, src
    i <- add i, 1
    j <- add j, 1
    loop
  }
]

scenario trim-unmodified [
  local-scope
  x:text <- new [abc]
  run [
    y:text <- trim x
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [abc]
  ]
]

scenario trim-left [
  local-scope
  x:text <- new [  abc]
  run [
    y:text <- trim x
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [abc]
  ]
]

scenario trim-right [
  local-scope
  x:text <- new [abc  ]
  run [
    y:text <- trim x
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [abc]
  ]
]

scenario trim-left-right [
  local-scope
  x:text <- new [  abc   ]
  run [
    y:text <- trim x
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [abc]
  ]
]

scenario trim-newline-tab [
  local-scope
  x:text <- new [	abc
]
  run [
    y:text <- trim x
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [abc]
  ]
]

def find-next text:text, pattern:char, idx:num -> next-index:num [
  local-scope
  load-inputs
  len:num <- length *text
  {
    eof?:bool <- greater-or-equal idx, len
    break-if eof?
    curr:char <- index *text, idx
    found?:bool <- equal curr, pattern
    break-if found?
    idx <- add idx, 1
    loop
  }
  return idx
]

scenario text-find-next [
  local-scope
  x:text <- new [a/b]
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 1
  ]
]

scenario text-find-next-empty [
  local-scope
  x:text <- new []
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 0
  ]
]

scenario text-find-next-initial [
  local-scope
  x:text <- new [/abc]
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 0  # prefix match
  ]
]

scenario text-find-next-final [
  local-scope
  x:text <- new [abc/]
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 3  # suffix match
  ]
]

scenario text-find-next-missing [
  local-scope
  x:text <- new [abcd]
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 4  # no match
  ]
]

scenario text-find-next-invalid-index [
  local-scope
  x:text <- new [abc]
  run [
    10:num/raw <- find-next x, 47/slash, 4/start-index
  ]
  memory-should-contain [
    10 <- 4  # no change
  ]
]

scenario text-find-next-first [
  local-scope
  x:text <- new [ab/c/]
  run [
    10:num/raw <- find-next x, 47/slash, 0/start-index
  ]
  memory-should-contain [
    10 <- 2  # first '/' of multiple
  ]
]

scenario text-find-next-second [
  local-scope
  x:text <- new [ab/c/]
  run [
    10:num/raw <- find-next x, 47/slash, 3/start-index
  ]
  memory-should-contain [
    10 <- 4  # second '/' of multiple
  ]
]

# search for a pattern of multiple characters
# fairly dumb algorithm
def find-next text:text, pattern:text, idx:num -> next-index:num [
  local-scope
  load-inputs
  first:char <- index *pattern, 0
  # repeatedly check for match at current idx
  len:num <- length *text
  {
    # does some unnecessary work checking even when there isn't enough of text left
    done?:bool <- greater-or-equal idx, len
    break-if done?
    found?:bool <- match-at text, pattern, idx
    break-if found?
    idx <- add idx, 1
    # optimization: skip past indices that definitely won't match
    idx <- find-next text, first, idx
    loop
  }
  return idx
]

scenario find-next-text-1 [
  local-scope
  x:text <- new [abc]
  y:text <- new [bc]
  run [
    10:num/raw <- find-next x, y, 0
  ]
  memory-should-contain [
    10 <- 1
  ]
]

scenario find-next-text-2 [
  local-scope
  x:text <- new [abcd]
  y:text <- new [bc]
  run [
    10:num/raw <- find-next x, y, 1
  ]
  memory-should-contain [
    10 <- 1
  ]
]

scenario find-next-no-match [
  local-scope
  x:text <- new [abc]
  y:text <- new [bd]
  run [
    10:num/raw <- find-next x, y, 0
  ]
  memory-should-contain [
    10 <- 3  # not found
  ]
]

scenario find-next-suffix-match [
  local-scope
  x:text <- new [abcd]
  y:text <- new [cd]
  run [
    10:num/raw <- find-next x, y, 0
  ]
  memory-should-contain [
    10 <- 2
  ]
]

scenario find-next-suffix-match-2 [
  local-scope
  x:text <- new [abcd]
  y:text <- new [cde]
  run [
    10:num/raw <- find-next x, y, 0
  ]
  memory-should-contain [
    10 <- 4  # not found
  ]
]

# checks if pattern matches at index 'idx'
def match-at text:text, pattern:text, idx:num -> result:bool [
  local-scope
  load-inputs
  pattern-len:num <- length *pattern
  # check that there's space left for the pattern
  x:num <- length *text
  x <- subtract x, pattern-len
  enough-room?:bool <- lesser-or-equal idx, x
  return-unless enough-room?, false/not-found
  # check each character of pattern
  pattern-idx:num <- copy 0
  {
    done?:bool <- greater-or-equal pattern-idx, pattern-len
    break-if done?
    c:char <- index *text, idx
    exp:char <- index *pattern, pattern-idx
    match?:bool <- equal c, exp
    return-unless match?, false/not-found
    idx <- add idx, 1
    pattern-idx <- add pattern-idx, 1
    loop
  }
  return true/found
]

scenario match-at-checks-pattern-at-index [
  local-scope
  x:text <- new [abc]
  y:text <- new [ab]
  run [
    10:bool/raw <- match-at x, y, 0
  ]
  memory-should-contain [
    10 <- 1  # match found
  ]
]

scenario match-at-reflexive [
  local-scope
  x:text <- new [abc]
  run [
    10:bool/raw <- match-at x, x, 0
  ]
  memory-should-contain [
    10 <- 1  # match found
  ]
]

scenario match-at-outside-bounds [
  local-scope
  x:text <- new [abc]
  y:text <- new [a]
  run [
    10:bool/raw <- match-at x, y, 4
  ]
  memory-should-contain [
    10 <- 0  # never matches
  ]
]

scenario match-at-empty-pattern [
  local-scope
  x:text <- new [abc]
  y:text <- new []
  run [
    10:bool/raw <- match-at x, y, 0
  ]
  memory-should-contain [
    10 <- 1  # always matches empty pattern given a valid index
  ]
]

scenario match-at-empty-pattern-outside-bound [
  local-scope
  x:text <- new [abc]
  y:text <- new []
  run [
    10:bool/raw <- match-at x, y, 4
  ]
  memory-should-contain [
    10 <- 0  # no match
  ]
]

scenario match-at-empty-text [
  local-scope
  x:text <- new []
  y:text <- new [abc]
  run [
    10:bool/raw <- match-at x, y, 0
  ]
  memory-should-contain [
    10 <- 0  # no match
  ]
]

scenario match-at-empty-against-empty [
  local-scope
  x:text <- new []
  run [
    10:bool/raw <- match-at x, x, 0
  ]
  memory-should-contain [
    10 <- 1  # matches because pattern is also empty
  ]
]

scenario match-at-inside-bounds [
  local-scope
  x:text <- new [abc]
  y:text <- new [bc]
  run [
    10:bool/raw <- match-at x, y, 1
  ]
  memory-should-contain [
    10 <- 1  # match
  ]
]

scenario match-at-inside-bounds-2 [
  local-scope
  x:text <- new [abc]
  y:text <- new [bc]
  run [
    10:bool/raw <- match-at x, y, 0
  ]
  memory-should-contain [
    10 <- 0  # no match
  ]
]

def split s:text, delim:char -> result:&:@:text [
  local-scope
  load-inputs
  # empty text? return empty array
  len:num <- length *s
  {
    empty?:bool <- equal len, 0
    break-unless empty?
    result <- new {(address array character): type}, 0
    return
  }
  # count #pieces we need room for
  count:num <- copy 1  # n delimiters = n+1 pieces
  idx:num <- copy 0
  {
    idx <- find-next s, delim, idx
    done?:bool <- greater-or-equal idx, len
    break-if done?
    idx <- add idx, 1
    count <- add count, 1
    loop
  }
  # allocate space
  result <- new {(address array character): type}, count
  # repeatedly copy slices start..end until delimiter into result[curr-result]
  curr-result:num <- copy 0
  start:num <- copy 0
  {
    # while next delim exists
    done?:bool <- greater-or-equal start, len
    break-if done?
    end:num <- find-next s, delim, start
    # copy start..end into result[curr-result]
    dest:text <- copy-range s, start, end
    *result <- put-index *result, curr-result, dest
    # slide over to next slice
    start <- add end, 1
    curr-result <- add curr-result, 1
    loop
  }
]

scenario text-split-1 [
  local-scope
  x:text <- new [a/b]
  run [
    y:&:@:text <- split x, 47/slash
    10:num/raw <- length *y
    a:text <- index *y, 0
    b:text <- index *y, 1
    20:@:char/raw <- copy *a
    30:@:char/raw <- copy *b
  ]
  memory-should-contain [
    10 <- 2  # length of result
    20:array:character <- [a]
    30:array:character <- [b]
  ]
]

scenario text-split-2 [
  local-scope
  x:text <- new [a/b/c]
  run [
    y:&:@:text <- split x, 47/slash
    10:num/raw <- length *y
    a:text <- index *y, 0
    b:text <- index *y, 1
    c:text <- index *y, 2
    20:@:char/raw <- copy *a
    30:@:char/raw <- copy *b
    40:@:char/raw <- copy *c
  ]
  memory-should-contain [
    10 <- 3  # length of result
    20:array:character <- [a]
    30:array:character <- [b]
    40:array:character <- [c]
  ]
]

scenario text-split-missing [
  local-scope
  x:text <- new [abc]
  run [
    y:&:@:text <- split x, 47/slash
    10:num/raw <- length *y
    a:text <- index *y, 0
    20:@:char/raw <- copy *a
  ]
  memory-should-contain [
    10 <- 1  # length of result
    20:array:character <- [abc]
  ]
]

scenario text-split-empty [
  local-scope
  x:text <- new []
  run [
    y:&:@:text <- split x, 47/slash
    10:num/raw <- length *y
  ]
  memory-should-contain [
    10 <- 0  # empty result
  ]
]

scenario text-split-empty-piece [
  local-scope
  x:text <- new [a/b//c]
  run [
    y:&:@:text <- split x:text, 47/slash
    10:num/raw <- length *y
    a:text <- index *y, 0
    b:text <- index *y, 1
    c:text <- index *y, 2
    d:text <- index *y, 3
    20:@:char/raw <- copy *a
    30:@:char/raw <- copy *b
    40:@:char/raw <- copy *c
    50:@:char/raw <- copy *d
  ]
  memory-should-contain [
    10 <- 4  # length of result
    20:array:character <- [a]
    30:array:character <- [b]
    40:array:character <- []
    50:array:character <- [c]
  ]
]

def split-first text:text, delim:char -> x:text, y:text [
  local-scope
  load-inputs
  # empty text? return empty texts
  len:num <- length *text
  {
    empty?:bool <- equal len, 0
    break-unless empty?
    x:text <- new []
    y:text <- new []
    return
  }
  idx:num <- find-next text, delim, 0
  x:text <- copy-range text, 0, idx
  idx <- add idx, 1
  y:text <- copy-range text, idx, len
]

scenario text-split-first [
  local-scope
  x:text <- new [a/b]
  run [
    y:text, z:text <- split-first x, 47/slash
    10:@:char/raw <- copy *y
    20:@:char/raw <- copy *z
  ]
  memory-should-contain [
    10:array:character <- [a]
    20:array:character <- [b]
  ]
]

def copy-range buf:text, start:num, end:num -> result:text [
  local-scope
  load-inputs
  # if end is out of bounds, trim it
  len:num <- length *buf
  end:num <- min len, end
  # allocate space for result
  len <- subtract end, start
  result:text <- new character:type, len
  # copy start..end into result[curr-result]
  src-idx:num <- copy start
  dest-idx:num <- copy 0
  {
    done?:bool <- greater-or-equal src-idx, end
    break-if done?
    src:char <- index *buf, src-idx
    *result <- put-index *result, dest-idx, src
    src-idx <- add src-idx, 1
    dest-idx <- add dest-idx, 1
    loop
  }
]

scenario copy-range-works [
  local-scope
  x:text <- new [abc]
  run [
    y:text <- copy-range x, 1, 3
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [bc]
  ]
]

scenario copy-range-out-of-bounds [
  local-scope
  x:text <- new [abc]
  run [
    y:text <- copy-range x, 2, 4
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- [c]
  ]
]

scenario copy-range-out-of-bounds-2 [
  local-scope
  x:text <- new [abc]
  run [
    y:text <- copy-range x, 3, 3
    1:@:char/raw <- copy *y
  ]
  memory-should-contain [
    1:array:character <- []
  ]
]

def parse-whole-number in:text -> out:num, error?:bool [
  local-scope
  load-inputs
  out <- copy 0
  result:num <- copy 0  # temporary location
  i:num <- copy 0
  len:num <- length *in
  {
    done?:bool <- greater-or-equal i, len
    break-if done?
    c:char <- index *in, i
    x:num <- character-to-code c
    digit:num, error?:bool <- character-code-to-digit x
    return-if error?
    result <- multiply result, 10
    result <- add result, digit
    i <- add i, 1
    loop
  }
  # no error; all digits were valid
  out <- copy result
]

# (contributed by Ella Couch)
recipe character-code-to-digit character-code:number -> result:number, error?:boolean [
  local-scope
  load-inputs
  result <- copy 0
  error? <- lesser-than character-code, 48  # '0'
  return-if error?
  error? <- greater-than character-code, 57  # '9'
  return-if error?
  result <- subtract character-code, 48
]

scenario character-code-to-digit-contain-only-digit [
  local-scope
  a:number <- copy 48  # character code for '0'
  run [
    10:number/raw, 11:boolean/raw <- character-code-to-digit a
  ]
  memory-should-contain [
    10 <- 0
    11 <- 0  # no error
  ]
]

scenario character-code-to-digit-contain-only-digit-2 [
  local-scope
  a:number <- copy 57  # character code for '9'
  run [
    1:number/raw, 2:boolean/raw <- character-code-to-digit a
  ]
  memory-should-contain [
    1 <- 9
    2 <- 0  # no error
  ]
]

scenario character-code-to-digit-handles-codes-lower-than-zero [
  local-scope
  a:number <- copy 47
  run [
    10:number/raw, 11:boolean/raw <- character-code-to-digit a
  ]
  memory-should-contain [
    10 <- 0
    11 <- 1  # error
  ]
]

scenario character-code-to-digit-handles-codes-larger-than-nine [
  local-scope
  a:number <- copy 58
  run [
    10:number/raw, 11:boolean/raw <- character-code-to-digit a
  ]
  memory-should-contain [
    10 <- 0
    11 <- 1  # error
  ]
]