(my-mins-between "11:30" "12:04")

(defun my-mins-between (time1 time2)
  "Return the minutes between HH:mm strings TIME1 and TIME2."
  (let ((diff (apply #'time-subtract
                     (mapcar (lambda (time)
                               (encode-time (decoded-time-set-defaults
                                             (parse-time-string time))))
                             (list time1 time2)))))
    (/ (float-time diff) 60)))

Debugger entered--Lisp error: (error "Invalid time specification")
  encode-time((0 30 11 1 1 0 nil -1 nil))
  (lambda (time) (encode-time (decoded-time-set-defaults (parse-time-string time))))("11:30")
  mapcar((lambda (time) (encode-time (decoded-time-set-defaults (parse-time-string time)))) ("11:30" "12:04"))


  In GNU Emacs 27.2 (build 1, x86_64-w64-mingw32)
 of 2021-03-26 built on CIRROCUMULUS
Repository revision: deef5efafb70f4b171265b896505b92b6eef24e6
Repository branch: HEAD
Windowing system distributor 'Microsoft Corp.', version 10.0.19041
System Description: Microsoft Windows 10 Home (v10.0.2004.19041.928)

Recent messages:
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my-mins-between
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user-error: Beginning of history; no preceding item
user-error: End of history; no default available
scroll-up-command: End of buffer
command-execute: Command attempted to use minibuffer while in minibuffer
Configured using:
 'configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static''

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY W32NOTIFY ACL GNUTLS LIBXML2
HARFBUZZ ZLIB TOOLKIT_SCROLL_BARS MODULES THREADS JSON PDUMPER LCMS2 GMP

Important settings:
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Major mode: Emacs-Lisp

Minor modes in effect:
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Load-path shadows:
c:/Users/pc/.emacs.d/elpa/flymake-1.1.1/flymake hides c:/Program Files/Emacs/x86_64/share/emacs/27.2/lisp/progmodes/flymake
c:/Users/pc/.emacs.d/elpa/eldoc-1.11.0/eldoc hides c:/Program Files/Emacs/x86_64/share/emacs/27.2/lisp/emacs-lisp/eldoc

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Memory information:
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