[ysh breaking] 1 .. 5 range replaced with 1..<5 half open and 1..=5 c…

…losed range (#2102)

This is issue #2096

display/pp_value.py

@@ -412,7 +412,7 @@ def _Value(self, val):
             elif case(value_e.Range):
                 r = cast(value.Range, val)
                 type_name = self._Styled(self.type_style, UText(ValType(r)))
-                mdocs = [UText(str(r.lower)), UText(".."), UText(str(r.upper))]
+                mdocs = [UText(str(r.lower)), UText("..<"), UText(str(r.upper))]
                 return self._SurroundedAndPrefixed("(", type_name, " ",
                                                    self._Join(mdocs, "", " "),
                                                    ")")

doc/error-catalog.md

@@ -207,6 +207,32 @@ standard boolean operators are written as `a and b`, `a or b` and `not a`.
 This differs from [command mode](command-vs-expression-mode.html) which uses
 shell-like `||` for "OR", `&&` for "AND" and `!` for "NOT".
 
+### OILS-ERR-16
+
+```
+  for x in (1 .. 5) {
+              ^~
+[ -c flag ]:1: Use ..< for half-open range, or ..= for closed range (OILS-ERR-16)
+```
+
+There are two ways to construct a [Range](ref/chap-expr-lang#range). The `..<`
+operator is for half-open ranges and the `..=` operator is for closed ranges:
+
+    for i in (0 ..< 3) {
+      echo $i
+    }
+    => 0
+    => 1
+    => 2
+
+    for i in (0 ..= 3) {
+      echo $i
+    }
+    => 0
+    => 1
+    => 2
+    => 3
+
 ## Runtime Errors - Traditional Shell
 
 These errors may occur in shells like [bash]($xref) and [zsh]($xref).

doc/ref/chap-expr-lang.md

@@ -231,21 +231,25 @@ the same name:
 
 ### range
 
-A range is a sequence of numbers that can be iterated over:
+A Range is a sequence of numbers that can be iterated over. The `..<` operator
+constructs half-open ranges.
 
-    for i in (0 .. 3) {
+    for i in (0 ..< 3) {
       echo $i
     }
     => 0
     => 1
     => 2
 
-As with slices, the last number isn't included.  To iterate from 1 to n, you
-can use this idiom:
+The `..=` operator constructs closed ranges:
 
-    for i in (1 .. n+1) {
+    for i in (0 ..= 3) {
       echo $i
     }
+    => 0
+    => 1
+    => 2
+    => 3
 
 ### block-expr
 

doc/ref/toc-ysh.md

@@ -262,7 +262,7 @@ X [External Lang] BEGIN   END   when (awk)
                   str-template  ^"$a and $b" for Str::replace()
                   list-literal  ['one', 'two', 3]  :| unquoted words |
                   dict-literal  {name: 'bob'}  {a, b}
-                  range         1 .. n+1
+                  range         1 ..< n  1 ..= n
                   block-expr    ^(echo $PWD)
                   expr-literal  ^[1 + 2*3]
                 X expr-sub      $[myobj]

doc/ysh-tour.md

@@ -453,7 +453,7 @@ Ask for the loop index:
 To iterate over a typed data, use parentheses around an **expression**.  The
 expression should evaluate to an integer `Range`, `List`, or `Dict`:
 
-    for i in (3 .. 5) {  # range operator ..
+    for i in (3 ..< 5) {  # range operator ..<
       echo "i = $i"
     }
     # =>
@@ -740,7 +740,7 @@ Here's a pure function:
 
     func myRepeat(s, n; special=false) {  # positional; named params
       var parts = []
-      for i in (0 .. n) {
+      for i in (0 ..< n) {
         append $s (parts)
       }
       var result = join(parts)

frontend/id_kind_def.py

@@ -232,7 +232,7 @@ def AddKinds(spec):
     #   $'\z'  Such bad codes are accepted when parse_backslash is on
     #          (default in OSH), so we have to lex them.
     #  (x == y) should used === or ~==
-    spec.AddKind('Unknown', ['Tok', 'Backslash', 'DEqual', 'DAmp', 'DPipe'])
+    spec.AddKind('Unknown', ['Tok', 'Backslash', 'DEqual', 'DAmp', 'DPipe', 'DDot'])
 
     spec.AddKind('Eol', ['Tok'])  # no more tokens on line (\0)
 
@@ -333,7 +333,8 @@ def AddKinds(spec):
             'Float',
             'Bang',  # eggex !digit, ![a-z]
             'Dot',
-            'DDot',
+            'DDotLessThan',
+            'DDotEqual',
             'Colon',  # mylist:pop()
             'RArrow',
             'RDArrow',

frontend/lexer_def.py

@@ -1103,10 +1103,12 @@ def R(pat, tok_type):
     C('//', Id.Expr_DSlash),  # For YSH integer division
     C('~==', Id.Expr_TildeDEqual),  # approximate equality
 
-    C('.', Id.Expr_Dot),      # d.key is alias for d['key']
-    C('..', Id.Expr_DDot),    # range 1..5
-    C('->', Id.Expr_RArrow),  # s->startswith()
-    C('$', Id.Expr_Dollar),   # legacy regex end: /d+ $/ (better written /d+ >/
+    C('.', Id.Expr_Dot),             # d.key is alias for d['key']
+    C('..', Id.Unknown_DDot),        # legacy half-open range 1..5
+    C('..<', Id.Expr_DDotLessThan),  # half-open range 1..<5
+    C('..=', Id.Expr_DDotEqual),     # closed range 1..5
+    C('->', Id.Expr_RArrow),         # s->startswith()
+    C('$', Id.Expr_Dollar),          # legacy regex end: /d+ $/ (better written /d+ >/
 
     # Reserved this.  Go uses it for channels, etc.
     # I guess it conflicts with -4<-3, but that's OK -- spaces suffices.

spec/ysh-bugs.test.sh

@@ -142,7 +142,7 @@ pp test_ (pipe())
 #### shvar then replace - bug #1986 context manager crash
 
 shvar FOO=bar {
-  for x in (1 .. 500) {
+  for x in (1 ..< 500) {
     var Q = "hello"
     setvar Q = Q=>replace("hello","world")
   }
@@ -239,20 +239,20 @@ case (WEIGHT) {
 
 proc p {
   var s = "hi"
-  for q in (1..50) {
+  for q in (1..<50) {
     shvar Q="whatever" {
       setvar s = "." ++ s
     }
   }
 }
 
-for i in (1..10) {
+for i in (1..<10) {
   p
 }
 
 if false {
   echo 'testing for longer'
-  for i in (1 .. 1000) {
+  for i in (1 ..< 1000) {
     p
   }
 }

spec/ysh-builtins.test.sh

@@ -638,7 +638,7 @@ echo $[type(f)]
 echo $[type(len)]
 echo $[type('foo'=>startsWith)]
 echo $[type('foo'=>join)]  # Type error happens later
-echo $[type(1..3)]
+echo $[type(1..<3)]
 ## STDOUT:
 Int
 Str

spec/ysh-closures.test.sh

@@ -50,7 +50,7 @@ proc task (; tasks, expr) {
 func makeTasks() {
   var tasks = []
   var x = 'x'
-  for __hack__ in (0 .. 3) {
+  for __hack__ in (0 ..< 3) {
     var i = __hack__
     var j = i + 2
     task (tasks, ^"$x: i = $i, j = $j")
@@ -82,7 +82,7 @@ proc task (; tasks; ; b) {
 func makeTasks() {
   var tasks = []
   var x = 'x'
-  for __hack__ in (0 .. 3) {
+  for __hack__ in (0 ..< 3) {
     var i = __hack__
     var j = i + 2
     task (tasks) { echo "$x: i = $i, j = $j" }
@@ -108,7 +108,7 @@ x: i = 2, j = 4
 shopt --set ysh:upgrade
 
 var procs = []
-for i in (0 .. 3) {
+for i in (0 ..< 3) {
   proc __invoke__ (; self) {
     echo "i = $[self.i]"
   }

spec/ysh-convert.test.sh

@@ -9,7 +9,7 @@ echo "$[bool({})]"
 echo "$[bool(null)]"
 echo "$[bool(len)]"
 echo "$[bool('foo'=>startsWith)]"
-echo "$[bool(1..3)]"
+echo "$[bool(1..<3)]"
 ## STDOUT:
 true
 false
@@ -180,7 +180,7 @@ foo
 #### list() from range
 shopt -s ysh:upgrade
 
-var mylist = list(0..3)
+var mylist = list(0..<3)
 write @mylist
 ## STDOUT:
 0

spec/ysh-for.test.sh

@@ -33,7 +33,7 @@ key age
 
 
 #### For loop over range
-var myrange = 0 .. 3
+var myrange = 0 ..< 3
 for i in (myrange) {
   echo "i $i"
 }

spec/ysh-func.test.sh

@@ -250,7 +250,7 @@ var cache = []
 var maxSize = 4
 
 func remove(l, i) {
-  for i in (i .. len(l) - 1) {
+  for i in (i ..< len(l) - 1) {
     setvar l[i] = l[i + 1]
   }
 

spec/ysh-int-float.test.sh

@@ -80,7 +80,7 @@ shopt -s ysh:upgrade
 # 1e-324 == 0.0 in Python
 
 var zeros = []
-for i in (1 .. 324) {
+for i in (1 ..< 324) {
   call zeros->append('0')
 }
 

spec/ysh-json.test.sh

@@ -1168,10 +1168,10 @@ shopt -s ysh:upgrade
 proc pairs(n) {
   var m = int(n)  # TODO: 1 .. n should auto-convert?
 
-  for i in (1 .. m) {
+  for i in (1 ..< m) {
     write -n -- '['
   }
-  for i in (1 .. m) {
+  for i in (1 ..< m) {
     write -n -- ']'
   }
 }

spec/ysh-list.test.sh

@@ -140,9 +140,9 @@ echo -$x-  # fails with type error
 ## END
 
 #### List->extend()
-var l = list(1..3)
+var l = list(1..<3)
 echo $[len(l)]
-call l->extend(list(3..6))
+call l->extend(list(3..<6))
 echo $[len(l)]
 ## STDOUT:
 2
@@ -151,9 +151,9 @@ echo $[len(l)]
 
 #### List append()/extend() should return null
 shopt -s ysh:all
-var l = list(1..3)
+var l = list(1..<3)
 
-var result = l->extend(list(3..6))
+var result = l->extend(list(3..<6))
 assert [null === result]
 
 setvar result = l->append(6)
@@ -166,7 +166,7 @@ pass
 
 #### List pop()
 shopt -s ysh:all
-var l = list(1..5)
+var l = list(1..<5)
 assert [4 === l->pop()]
 assert [3 === l->pop()]
 assert [2 === l->pop()]

spec/ysh-methods.test.sh

@@ -584,7 +584,7 @@ pp test_ (c)
 ## END
 
 #### List->reverse() from iterator
-var x = list(0 .. 3)
+var x = list(0 ..< 3)
 call x->reverse()
 write @x
 ## STDOUT:

spec/ysh-printing.test.sh

@@ -35,11 +35,11 @@
 ## END
 
 #### Range
-var x = 1..100
+var x = 1..<100
 
 pp value (x)
 
-# TODO: show type here, like (Range 1 .. 100)
+# TODO: show type here, like (Range 1 ..< 100)
 
 pp value ({k: x})
 
@@ -49,8 +49,8 @@ pp test_ (x)
 pp test_ ({k: x})
 
 ## STDOUT:
-(Range 1 .. 100)
-(Dict)  {k: (Range 1 .. 100)}
+(Range 1 ..< 100)
+(Dict)  {k: (Range 1 ..< 100)}
 
 <Range>
 (Dict)   {"k":<Range>}

spec/ysh-regex-api.test.sh

@@ -752,7 +752,7 @@ shopt --set ysh:all
 
 var mystr = '1abc2abc3abc'
 
-for count in (-2..4) {
+for count in (-2..<4) {
   write $[mystr.replace('abc', "-", count=count)]
   write $[mystr.replace('abc', ^"-", count=count)]
   write $[mystr.replace(/ [a-z]+ /, "-", count=count)]