CONTENTS 1 Using Lean 1 1.1 Using Lean Online 1 1.2 Using Lean with VSCode 1 1.3 Using Lean with Emacs 2 1.4 Using the Package Manager 3 2 Lexical Structure 7 2.1 Symbols and Commands 7 2.2 Identifiers to open the root directory for the project. ### 1.3 Using Lean with Emacs Assuming you have installed Lean, Emacs, and the Lean Emacs mode according to the instructions on the Lean Download page, you simply simply need to create a file with the extension .lean and edit it in Emacs. The file will be checked continuously as you type. For example, if you type the words #check id, the word #check is underlined

of the tokens print axioms : display assumed axioms print options : display options set by user or emacs mode print prefix : display all declarations in the namespace print coercions : display : execute a single tactic with different options ( is a comma-separated list) ## Emacs Lean-mode commands ## Flycheck commandsEmacs Lean mode. ## Logical symbols |Unicode|Ascii|Emacs| |---|---|---| |true||| |false||| |¬|not|\\not, \\neg| |^|/\\\\|\\and|

4.1 Automatic Proof Search (Auto) 111 4.2 Command-line options 114 4.3 Compilers 118 4.4 Emacs Mode 120 4.5 Literate Programming 125 4.6 Generating HTML 127 4.7 Generating LaTeX 127 4.8 Alex: https://www.haskell.org/alex/ • Happy: https://www.haskell.org/happy/ • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your shell's search path. For instructions on installing a suitable version of Emacs under Windows, see Installing Emacs under Windows. Non-Windows users need to ensure that the development files for

Proof Search (Auto) ..... 141 4.2 Command-line options ..... 144 4.3 Compilers ..... 150 4.4 Emacs Mode ..... 152 4.5 Literate Programming ..... 157 4.6 Generating HTML ..... 159 4.7 Generating Alex: https://www.haskell.org/alex/ • Happy: https://www.haskell.org/happy/ • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your your shell’s search path. For instructions on installing a suitable version of Emacs under Windows, see Installing Emacs under Windows. Non-Windows users need to ensure that the development files for the

o Without K ## • Tools • Automatic Proof Search (Auto) Command-line options Compilers ○ Emacs Mode • Literate Programming Generating HTML Generating LaTeX Library Management • Contribute system can be used can be found in chapter Tools. ## Getting Started • Prerequisites Installing Emacs under Windows • Installation Installation from Hackage ○ Prebuilt Packages and System-Specific Alex: https://www.haskell.org/alex/ • Happy: https://www.haskell.org/happy/ • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your

o Without K ## • Tools • Automatic Proof Search (Auto) Command-line options Compilers ○ Emacs Mode • Literate Programming Generating HTML Generating LaTeX Library Management • Contribute system can be used can be found in chapter Tools. ## Getting Started • Prerequisites Installing Emacs under Windows • Installation Installation from Hackage ○ Prebuilt Packages and System-Specific https://www.haskell.org/happy/ • cpphs: https://hackage.haskell.org/package/cpphs • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your

o Without K ## • Tools • Automatic Proof Search (Auto) Command-line options Compilers ○ Emacs Mode • Literate Programming Generating HTML Generating LaTeX Library Management • Contribute system can be used can be found in chapter Tools. ## Getting Started • Prerequisites Installing Emacs under Windows • Installation Installation from Hackage ○ Prebuilt Packages and System-Specific https://www.haskell.org/happy/ • cpphs: https://hackage.haskell.org/package/cpphs • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your

4.1 Automatic Proof Search (Auto) 111 4.2 Command-line options 114 4.3 Compilers 118 4.4 Emacs Mode 120 4.5 Literate Programming 125 4.6 Generating HTML 127 4.7 Generating LaTeX 127 4.8 https://www.haskell.org/happy/ • cpphs: https://hackage.haskell.org/package/cpphs • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your your shell’s search path. For instructions on installing a suitable version of Emacs under Windows, see Installing Emacs under Windows. Non-Windows users need to ensure that the development files for the

4.1 Automatic Proof Search (Auto) 111 4.2 Command-line options 114 4.3 Compilers 118 4.4 Emacs Mode 120 4.5 Literate Programming 125 4.6 Generating HTML 127 4.7 Generating LaTeX 127 4.8 https://www.haskell.org/happy/ • cpphs: https://hackage.haskell.org/package/cpphs • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your your shell’s search path. For instructions on installing a suitable version of Emacs under Windows, see Installing Emacs under Windows. Non-Windows users need to ensure that the development files for the

With-Abstraction ☐ Without K ## • Tools • Automatic Proof Search (Auto) Command-line options • Compilers ○ Emacs Mode • Literate Programming Generating HTML Generating LaTeX Library Management • Contribute chapter Tools. ## Getting Started • What is Agda? Dependent types • Prerequisites Installing Emacs under Windows • Installation Installation from Hackage ○ Prebuilt Packages and System-Specific Alex: https://www.haskell.org/alex/ • Happy: https://www.haskell.org/happy/ • GNU Emacs: http://www.gnu.org/software/emacs/ You should also make sure that programs installed by cabal-install are on your