Width and height argtypes, kdesc --argtypes from ref/, txt @define/@left_right/@columns, kdiag --check value validation (from dev d6993110e9b3)

Also: the klammertext argtype (descriptions kept as source), txt table
wrapping and :hpos/:offset, @c between ‹ ›, txt section headings, the
ktext newline-only trim, capitalize(), and the argtype test suite.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

sks/block/block.k

@@ -31,10 +31,10 @@ vertical mode is a no-op.
 
 # Indented block
 
-@@indent.k s :left.int 8 :right.int -1 :ragged.bool false :
-Indented block. The *left* and *right* values are the number of characters for
-indentation (as roughtly defined by "ex"). By default, *right* is set to the
-*left* value (with -1 as the sentinel).
+@@indent.k s :left.width 8 :right.width :ragged.bool false :
+Indented block. *left* and *right* are widths: a bare number is that many
+characters (the width of a digit in a proportional typeface), or a width
+with a unit such as 2em. *right* defaults to the *left* value.
 @@
 @@indent.html,tex,txt :: @eval block.Indent(K) eval@ @@
 
@@ -124,13 +124,12 @@ indentation (as roughtly defined by "ex"). By default, *right* is set to the
 @@extendpage.tex :: \enlargethispage{*linecount*\baselineskip} @@
 @@extendpage.txt :: @@
 
-
 # Vertical space
 
-@@vspace.k lines.float : Vertical space, in multiples of the current line height @@
-@@vspace.tex :: \vspace{*lines*\baselineskip} @@
-@@vspace.html :: <div style="height: *lines*lh"></div> @@
-@@vspace.txt :: @eval phases.txt_vspace_marker() * round(*lines*) @ @@
+# The first parameter of the height type: a bare number is lines in every
+# target (as it always was here), and a unit may now be given.
+@@vspace.k lines.height : Vertical space: a number of lines, or a height such as 2em @@
+@@vspace.html,tex,txt :: @eval block.Vspace(K) @ @@
 
 # Vertical fill to end of page
 
@@ -146,6 +145,10 @@ only makes some vertical space. @@
 @@vfill.html :: <div class="vfill"></div> @@
 @@vfill.txt :: @vspace 3 @ @@
 
+# Horizontal space
+@@hspace.k width.width : Horizontal space of the given *width* (a bare number is characters) @@
+@@hspace.html,tex,txt :: @eval block.Hspace(K) @ @@
+
 
 # Questions and answers
 
@@ -202,7 +205,7 @@ bar (|) between each line. Then, two bars (||), and the right lines with a bar
 betwen them.
 @@
 
-@@left_right.html,tex :: @eval block.Left_right(K) @ @@
+@@left_right.html,tex,txt :: @eval block.Left_right(K) @ @@
 
 
 # Footnote

sks/block/block.py

@@ -11,35 +11,56 @@ from html_util import E
 import color
 
 class Indent(klammer_base.Klammer_base):
+    """An indented block (@indent).  :left and :right are widths: a bare
+    number is characters in every target (2026-09-16); :right defaults to
+    :left."""
     def __init__(self, K):
         super().__init__(K)
-        # Doesn't do anything now:
-        # self.s = kutil.escape(self.s)
-        if self.right < 0:
+        if not self.right:
             self.right = self.left
-        self.reduce = self.left + self.right
 
     def html(self):
         text_align = "justify" if not self.ragged else "left"
+        left = kutil.parse_width("html", self.left)[0]
+        right = kutil.parse_width("html", self.right)[0]
         return E("div").body(self.s)\
-                       .sty("margin", f"0.5rem {self.right}ex 0.5rem {self.left}ex")\
+                       .sty("margin", f"0.5rem {right} 0.5rem {left}")\
                        .sty("text-align", text_align)\
                        .str()
     def tex(self):
         if self.ragged:
             self.s = "\\raggedright " + self.s
-        result = rf"\hspace*{{{self.left}ex}}" + latex_util.minipage(
-            self.s, rf"\linewidth - {self.reduce}ex", center=False)
+        left = kutil.parse_width("tex", self.left)[0]
+        right = kutil.parse_width("tex", self.right)[0]
+        result = rf"\hspace*{{{left}}}" + latex_util.minipage(
+            self.s, rf"\linewidth - {left} - {right}", center=False)
         result = latex_util.block(result)
         return result
 
     def txt(self):
-        indent = phases.txt_nbsp_marker() * self.left  # a space that survives
-        width = int(self.Target_txt_width) - self.left - self.right + 1 # Off-by one for textwrap
-        result = self.s
-        result = re.sub("KK0022", '"', result)
-        result = indent + f"\n{indent}".join(textwrap.wrap(result, width=width, break_on_hyphens=True))
-        return result
+        left = int(kutil.parse_width("txt", self.left)[0])
+        right = int(kutil.parse_width("txt", self.right)[0])
+        indent = phases.txt_nbsp_marker() * left  # a space that survives
+        width = int(self.Target_txt_width) - left - right
+        result = re.sub("KK0022", '"', self.s)
+        return phases.txt_lay_out(indent + f"\n{indent}".join(phases.txt_wrap(result, width)))
+
+class Hspace(klammer_base.Klammer_base):
+    """Horizontal space (@hspace): a width, so a bare number is characters
+    in every target."""
+    def __init__(self, K):
+        super().__init__(K)
+
+    def html(self):
+        return f'<span style="display: inline-block; width: {kutil.parse_width("html", self.width)[0]}"></span>'
+
+    def tex(self):
+        return f"\\hspace{{{kutil.parse_width('tex', self.width)[0]}}}"
+
+    def txt(self):
+        # The nbsp marker, not spaces: an @eval result of only whitespace
+        # is trimmed away entirely.
+        return phases.txt_nbsp_marker() * int(kutil.parse_width("txt", self.width)[0])
     
 
 class Note(klammer_base.Klammer_base):
@@ -106,6 +127,26 @@ class Lines(klammer_base.Klammer_base):
     def txt(self):
         return self.lines
 
+class Vspace(klammer_base.Klammer_base):
+    """Vertical space (@vspace): the first parameter of the height type.  A
+    bare number is lines in every target, as it always was here; a unit
+    (2em, 12pt) is now accepted as well, under html and tex."""
+    def __init__(self, K):
+        super().__init__(K)
+
+    def html(self):
+        height = kutil.parse_height("html", self.lines)[0]
+        return f'<div style="{kutil.css_height("height", height)}"></div>'
+
+    def tex(self):
+        return f"\\vspace{{{kutil.parse_height('tex', self.lines)[0]}}}"
+
+    def txt(self):
+        # One marker per line; the justification phase turns them into
+        # blank lines after paragraph normalization (a whitespace-only
+        # @eval result would be trimmed away, hence the markers).
+        return phases.txt_vspace_marker() * int(kutil.parse_height("txt", self.lines)[0])
+
 class Left_right(klammer_base.Klammer_base):
     def __init__(self, K):
         super().__init__(K)
@@ -126,3 +167,23 @@ class Left_right(klammer_base.Klammer_base):
             result += rf"\parbox{{\linewidth}}{{{left} \hfill {right}}}" + " \\\\\n"
         result = result[:-3]
         return result
+
+    def txt(self):
+        # Plain text: the left text at the block indent, the right text ending
+        # at Target_txt_width, the gap filled with the nbsp marker (the only
+        # space that survives to the output, and what marks the block as laid
+        # out).  A pair that cannot share a line -- less than two columns
+        # between them -- goes on two lines, the right text still flush right.
+        nbsp = phases.txt_nbsp_marker()
+        indent = int(self.Target_txt_indent)
+        width = int(self.Target_txt_width)
+        lines = []
+        for left, right in self.rows:
+            left, right = left.strip(), right.strip()
+            gap = width - indent - phases.txt_visible_length(left) - phases.txt_visible_length(right)
+            if gap >= 2:
+                lines.append(nbsp * indent + left + nbsp * gap + right)
+            else:
+                lines.append(nbsp * indent + left)
+                lines.append(nbsp * max(indent, width - phases.txt_visible_length(right)) + right)
+        return phases.txt_lay_out("\n".join(lines))