Note: I am running this with the following hook removed: (add-hook 'eshell-mode-hook (lambda () (remove-hook 'eshell-alternate-command-hook 'eshell-fix-bad-commands t))) However, not removing it makes no difference to the behavior, the error visibility would be postponed until the 4th try, when eshell asks to provide an alias (making everything even more confusing). =========== Bug report: =========== All behavior of comparisons below is incorrect # Comparisons using ">" ### 1. ~/tmp $ ${> 3 2} Actual: nil: command not found: command not found Expected: t: command not found (same as below in pure elisp) ~/tmp $ $(> 3 2) # pure elisp Actual equals Expected: t: command not found ### 2. ~/tmp $ {> 3 2} Actual: nil: command not found Expected: t ### 3. ~/tmp $ > 3 2 nil: command not found Expected: t # the above shows incorrect result, which can be tested also as follows ### 4. ~/tmp $ if {> 3 2} {echo YES} {echo NO} Actual: NO Expected: YES # Reverse comparisons using "<" ### 5. ~/tmp $ ${< 3 2} Actual: Eshell does not support input redirection Expected: nil: command not found ### 6. ~/tmp $ {< 3 2} Actual: Eshell does not support input redirection Expected: no result, as in (< 3 2) ### 7. ~/tmp $ < 3 2 Actual: Eshell does not support input redirection Expected: nil: command not found Expected: no result, as in (< 3 2) ### 8. The above shows incorrect results, which can be tested in # variants of the following: ~/tmp $ if {< 3 2} {echo YES} {echo NO} Actual: Eshell does not support input redirection Expected: NO In GNU Emacs 29.0.50 (build 1, x86_64-suse-linux-gnu, GTK+ Version 3.24.34, cairo version 1.17.6) System Description: openSUSE Tumbleweed Configured using: 'configure --host=x86_64-suse-linux-gnu --build=x86_64-suse-linux-gnu --program-prefix= --disable-dependency-tracking --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib64 --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/var/lib --mandir=/usr/share/man --infodir=/usr/share/info --disable-build-details --without-pop --with-mailutils --without-hesiod --with-gameuser=:games --with-kerberos --with-kerberos5 --with-file-notification=inotify --with-modules --enable-autodepend --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --datadir=/usr/share --localstatedir=/var --sharedstatedir=/var/lib --libexecdir=/usr/libexec --with-file-notification=yes --enable-locallisppath=/usr/share/emacs/29.0.50/site-lisp:/usr/share/emacs/site-lisp --without-x --with-json --without-xim --with-sound --with-xpm --with-jpeg --with-tiff --with-gif --with-png --with-rsvg --with-dbus --without-xft --without-gpm --with-pgtk --without-native-compilation --with-toolkit-scroll-bars --with-libotf --with-m17n-flt --with-cairo --without-xwidgets --with-dumping=pdumper 'CFLAGS=-O2 -Wall -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 -fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables -fstack-clash-protection -Werror=return-type -flto=auto -D_GNU_SOURCE -DGDK_DISABLE_DEPRECATION_WARNINGS -DGLIB_DISABLE_DEPRECATION_WARNINGS' LDFLAGS=-flto=auto' Configured features: ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2 MODULES NOTIFY INOTIFY PDUMPER PGTK PNG RSVG SECCOMP SOUND SQLITE3 THREADS TIFF TOOLKIT_SCROLL_BARS WEBP XIM GTK3 ZLIB Important settings: value of $LANG: en_CA.UTF-8 value of $XMODIFIERS: @im=ibus locale-coding-system: utf-8-unix Major mode: Eshell Minor modes in effect: shell-dirtrack-mode: t eshell-prompt-mode: t eshell-hist-mode: t eshell-pred-mode: t eshell-cmpl-mode: t eshell-proc-mode: t eshell-arg-mode: t tooltip-mode: t global-eldoc-mode: t show-paren-mode: t electric-indent-mode: t mouse-wheel-mode: t tool-bar-mode: t menu-bar-mode: t file-name-shadow-mode: t global-font-lock-mode: t font-lock-mode: t blink-cursor-mode: t line-number-mode: t indent-tabs-mode: t transient-mark-mode: t auto-composition-mode: t auto-encryption-mode: t auto-compression-mode: t Load-path shadows: None found. Features: (shadow sort mail-extr emacsbug message mailcap yank-media puny dired dired-loaddefs rfc822 mml mml-sec password-cache epa derived epg rfc6068 epg-config gnus-util text-property-search time-date mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils cl-seq rx em-unix em-term term disp-table shell subr-x ehelp em-script em-prompt em-ls em-hist em-pred em-glob em-extpipe em-cmpl em-dirs esh-var pcomplete comint ansi-osc ansi-color ring em-basic em-banner em-alias esh-mode eshell esh-cmd generator esh-ext esh-opt esh-proc esh-io esh-arg esh-module esh-groups esh-util cus-edit pp cus-start cus-load icons wid-edit cl-loaddefs cl-lib files-x rmc iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook vc-hooks lisp-float-type elisp-mode mwheel term/pgtk-win pgtk-win term/common-win pgtk-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu timer select scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors frame minibuffer nadvice seq simple cl-generic indonesian philippine cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech european ethiopic indian cyrillic chinese composite emoji-zwj charscript charprop case-table epa-hook jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs theme-loaddefs faces cus-face macroexp files window text-properties overlay sha1 md5 base64 format env code-pages mule custom widget keymap hashtable-print-readable backquote threads dbusbind inotify dynamic-setting system-font-setting font-render-setting cairo gtk pgtk lcms2 multi-tty make-network-process emacs) Memory information: ((conses 16 78484 13781) (symbols 48 8942 0) (strings 32 24745 2566) (string-bytes 1 734947) (vectors 16 15111) (vector-slots 8 205050 17892) (floats 8 35 34) (intervals 56 421 0) (buffers 984 11))