improve substring indexing

root_name: dedupe code paths

Author: scivision

+stdlib/expanduser.m

@@ -30,7 +30,7 @@
 if ischar(e)
   e = strcat(home, '/', e(3:end));
 else
-  e = home + "/" + extractAfter(e, 2);
+  e = home + "/" + e{1}(3:end);
 end
 
 end

+stdlib/is_absolute.m

@@ -22,7 +22,7 @@
   if ischar(p)
     s = p(3); %#ok<UNRCH>
   else
-    s = extractBetween(p, 3, 3);
+    s = p{1}(3);
   end
   y = strlength(stdlib.root_name(p)) && (strcmp(s, '/') || strcmp(s, '\'));
 else

+stdlib/normalize.m

@@ -43,7 +43,7 @@
       if isempty(j)
         n = "";
       else
-        n = extractBefore(n, j(end));
+        n = n{1}(1:j(end)-1);
       end
     end
   elseif all(parts(i) ~= [".", ""])

+stdlib/parent.m

@@ -34,7 +34,7 @@
 elseif ischar(p)
   p = p(1:j(end)-1);
 else
-  p = extractBefore(p, j(end));
+  p = p{1}(1:j(end)-1);
 end
 
 if is_root_stub(p)

+stdlib/private/h5save_scalar.m

@@ -44,9 +44,9 @@ function h5save_scalar(file, hpath, A)
   case 'double', t = 'H5T_NATIVE_DOUBLE';
   case 'single', t = 'H5T_NATIVE_FLOAT';
   case {'int8', 'int16', 'int32', 'int64'}
-    t = "H5T_STD_I" + extractBetween(C, 4, strlength(C)) + "LE";
+    t = "H5T_STD_I" + C(4:end) + "LE";
   case {'uint8', 'uint16', 'uint32', 'uint64'}
-    t = "H5T_STD_U" + extractBetween(C, 5, strlength(C)) + "LE";
+    t = "H5T_STD_U" + C(5:end) + "LE";
   otherwise, error('h5save:class2h5t: unknown data class %s', class(A))
 end
 

+stdlib/private/strlength.m

@@ -3,12 +3,13 @@
 % for GNU Octave until it builds in strlength
 
 function L = strlength(s)
-
-L = [];
+arguments
+  s {mustBeTextScalar}
+end
 
 if ischar(s)
   L = length(s);
-elseif isstring(s)
+else
   L = builtin('strlength', char(s));
   % bug in Matlab at least through R2025a confirmed by Xinyue Xia of Mathworks Technical Support
   % only works for char and scalar strings until fixed by Mathworks.

+stdlib/root_name.m

@@ -7,21 +7,23 @@
 
 function r = root_name(p)
 arguments
-  p (1,1) string
+  p {mustBeTextScalar}
 end
 
 r = "";
 
-if ~ispc || strlength(p) < 2, return, end
+if ~ispc || strlength(p) < 2
+  return
+end
+
+c = char(p);
+
+if c(2) == ':' && isletter(c(1))
+  r = c(1:2);
+end
 
-if ischar(p)
-  if p(2) == ':' && isletter(p(1)) %#ok<UNRCH>
-    r = p(1:2);
-  end
-else
-  if extractBetween(p, 2, 2) == ":" && isletter(extractBetween(p, 1, 1))
-    r = extractBetween(p, 1, 2);
-  end
+if isstring(p)
+  r = string(r);
 end
 
 end

private/publish_gen_index_html.m

@@ -24,7 +24,7 @@ function publish_gen_index_html(pkg_name, tagline, project_url, outdir)
 
 %% Git info
 repo = gitrepo(pkg.path);
-git_txt = "Git branch / commit: " + repo.CurrentBranch.Name + " " + extractBefore(repo.LastCommit.ID, 8);
+git_txt = "Git branch / commit: " + repo.CurrentBranch.Name + " " + repo.LastCommit.ID{1}(1:8);
 
 %% generate docs
 readme = fullfile(outdir, "index.html");