5 files changed, 38 insertions(+), 5 deletions(-)

M src/xidoc.nim
M src/xidocpkg/error.nim
M src/xidocpkg/expand.nim
M src/xidocpkg/parser.nim
M src/xidocpkg/types.nim

@@ 29,6 29,8 @@ proc renderXidoc*(body: string, path = "", target = tHtml, snippet = false, safe
     verbose: verbose,
     stack: @[Frame(
       cmdName: "[top]",
+      cmdPos: body.low..body.high,
+      cmdArgPos: body.low..body.high,
       path: some(path),
     )]
   )

@@ 15,6 15,18 @@ proc xidocWarning*(msge: string) =
   when not defined(js):
     stderr.writeLine("Warning: " & msge)
 
+func posToCoords(body: string, pos: int): tuple[row, col: int] =
+  var newlines = 0
+  var lastNewline = -1
+  for i in 0..<pos:
+    if body[i] == '\n':
+      newlines.inc
+      lastNewline = i
+  return (newlines + 1, pos - lastNewline)
+
+func formatPos(pos: tuple[row, col: int]): string =
+  &"{pos.row}:{pos.col}"
+
 proc format*(err: XidocError, doc: Document, termColors: bool): FormattedXidocError =
   const
     red = "\e[91m"


@@ 35,7 47,9 @@ proc format*(err: XidocError, doc: Document, termColors: bool): FormattedXidocEr
       let numOpeningBrackets = truncatedArg.count('[')
       let numClosingBrackets = truncatedArg.count(']')
       truncatedArg.add "]…".repeat(numOpeningBrackets - numClosingBrackets)
-    msg &= &"in [{frame.cmdName}{truncatedArg}]\n"
+    let posA = posToCoords(doc.body, frame.cmdPos.a).formatPos
+    let posB = posToCoords(doc.body, frame.cmdPos.b).formatPos
+    msg &= &"[{posA}–{posB}] in [{frame.cmdName}{truncatedArg}]\n"
   if termColors:
     msg &= reset
   msg &= err.msg

@@ 6,6 6,9 @@ import std/options
 import std/strformat
 import std/strutils
 
+proc `+`(s: Slice[int], n: int): Slice[int] =
+  s.a + n .. s.b + n
+
 proc escapeText*(text: string, target: Target): string =
   case target
   of tHtml:


@@ 58,7 61,10 @@ proc expand*(doc: Document, str: string, typ: XidocType): XidocValue =
         let name = node.name
         let command = doc.lookup(commands, name)
         ifSome command:
-          var frame = Frame(cmdName: name, cmdArg: node.arg)
+          let offset = doc.stack[^1].cmdArgPos.a
+          var frame = Frame(cmdName: name, cmdArg: node.arg,
+                            cmdPos: node.pos + offset,
+                            cmdArgPos: node.argPos + offset)
           doc.stack.add frame
           let val = command(node.arg)
           discard doc.stack.pop

@@ 8,6 8,7 @@ type
     xnkWhitespace
     xnkCommand
   XidocNode* = object
+    pos*: Slice[int]
     case kind*: XidocNodeKind
     of xnkString:
       str*: string


@@ 16,6 17,7 @@ type
     of xnkCommand:
       name*: string
       arg*: string
+      argPos*: Slice[int]
   XidocNodes* = seq[XidocNode]
 
 const nonTextChars = Whitespace + {'[', ']'}


@@ 62,17 64,20 @@ proc parseXidocString(body: string, i: var int): XidocNode =
   ## Finds a string of non-whitespace non-brackets characters in `body`,
   ## starting from position `i` and leaving `i` after the found substring.
   ## Returns a `XidocNode` with kind `xnkString`.
-  XidocNode(kind: xnkString, str: parseXidocStringHelper(body, i))
+  let start = i
+  let str = parseXidocStringHelper(body, i)
+  XidocNode(pos: start..<i, kind: xnkString, str: str)
 
 proc parseXidocWhitespace(body: string, i: var int): XidocNode =
   ## Finds a string of whitespace characters in `body`,
   ## starting from position `i` and leaving `i` after the found substring.
   ## Returns a `XidocNode` with kind `xnkWhitespace`.
+  let start = i
   var newline = false
   while i <= body.high and body[i] in Whitespace:
     newline = newline or body[i] == '\n'
     i.inc
-  XidocNode(kind: xnkWhitespace, newline: newline)
+  XidocNode(pos: start..<i, kind: xnkWhitespace, newline: newline)
 
 proc parseXidocCommand(body: string, i: var int): XidocNode =
   ## Finds a xidoc command in `body`,


@@ 80,6 85,7 @@ proc parseXidocCommand(body: string, i: var int): XidocNode =
   ## `body[i]` must be '[' at the start.
   ## Returns a `XidocNode` with kind `xnkCommand`.
   assert body[i] == '['
+  let start = i
   i.inc
   let name = parseXidocStringHelper(body, i)
   if i > body.high:


@@ 91,7 97,10 @@ proc parseXidocCommand(body: string, i: var int): XidocNode =
   skipBalancedText(body, i)
   if i > body.high:
     xidocError "Parse error: Unexpected end of file (did you forget to close a bracket?)"
-  result = XidocNode(kind: xnkCommand, name: name, arg: body[argStart..<i])
+  result = XidocNode(
+    pos: start..<i+1,
+    kind: xnkCommand, name: name, arg: body[argStart..<i], argPos: argStart..<i
+  )
   i.inc
 
 proc parseXidoc*(body: string, verbose = false): XidocNodes =

@@ 35,6 35,8 @@ type
     args*: Table[string, string]
     cmdArg*: string
     cmdName*: string
+    cmdPos*: Slice[int]
+    cmdArgPos*: Slice[int]
     commands*: Table[string, Command]
     lang*: Option[Language]
     path*: Option[string]