Fix build error with new mojo version

[kp992]

Fixes #17

[kp992]

@mmcky These are the updates that fixes the build error for me locally with the following mojo version.

Logs

% jb build ./      
Running Jupyter-Book v0.15.1
Source Folder: /Users/kpl/repos/project.lecture-mojo
Config Path: /Users/kpl/repos/project.lecture-mojo/_config.yml
Output Path: /Users/kpl/repos/project.lecture-mojo/_build/html
Running Sphinx v5.0.2
making output directory... done
[etoc] Changing master_doc to 'intro'
myst v0.18.1: MdParserConfig(commonmark_only=False, gfm_only=False, enable_extensions=['colon_fence', 'dollarmath', 'linkify', 'substitution', 'tasklist'], disable_syntax=[], all_links_external=False, url_schemes=['mailto', 'http', 'https'], ref_domains=None, highlight_code_blocks=True, number_code_blocks=[], title_to_header=False, heading_anchors=None, heading_slug_func=None, footnote_transition=True, words_per_minute=200, sub_delimiters=('{', '}'), linkify_fuzzy_links=True, dmath_allow_labels=True, dmath_allow_space=True, dmath_allow_digits=True, dmath_double_inline=False, update_mathjax=True, mathjax_classes='tex2jax_process|mathjax_process|math|output_area')
myst-nb v0.17.2: NbParserConfig(custom_formats={}, metadata_key='mystnb', cell_metadata_key='mystnb', kernel_rgx_aliases={}, execution_mode='cache', execution_cache_path='', execution_excludepatterns=[], execution_timeout=600, execution_in_temp=False, execution_allow_errors=False, execution_raise_on_error=False, execution_show_tb=False, merge_streams=False, render_plugin='default', remove_code_source=False, remove_code_outputs=False, code_prompt_show='Show code cell {type}', code_prompt_hide='Hide code cell {type}', number_source_lines=False, output_stderr='show', render_text_lexer='myst-ansi', render_error_lexer='ipythontb', render_image_options={}, render_figure_options={}, render_markdown_format='commonmark', output_folder='build', append_css=True, metadata_to_fm=False)
Using jupyter-cache at: /Users/kpl/repos/project.lecture-mojo/_build/.jupyter_cache
building [mo]: targets for 0 po files that are out of date
building [html]: targets for 6 source files that are out of date
updating environment: [new config] 6 added, 0 changed, 0 removed
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md: Executing notebook using local CWD [mystnb]
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md: Executed notebook in 3.10 seconds [mystnb]
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md: Cached executed notebook: ID=1 [mystnb]
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md: Executing notebook using local CWD [mystnb]
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md: Executed notebook in 2.74 seconds [mystnb]
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md: Cached executed notebook: ID=2 [mystnb]
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb: Executing notebook using local CWD [mystnb]
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb: Executed notebook in 2.31 seconds [mystnb]
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb: Cached executed notebook: ID=3 [mystnb]
/Users/kpl/repos/project.lecture-mojo/intro.md: Executing notebook using local CWD [mystnb]
/Users/kpl/repos/project.lecture-mojo/intro.md: Executed notebook in 1.00 seconds [mystnb]
/Users/kpl/repos/project.lecture-mojo/intro.md: Cached executed notebook: ID=4 [mystnb]
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md: Executing notebook using local CWD [mystnb]
[ErrorLog] Failed to parse the module
[ErrorLog] Expression [3]:3:5: expression must be mutable for in-place operator destination
    x += 1
    ^

/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md: Executed notebook in 2.61 seconds [mystnb]
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md: Cached executed notebook: ID=5 [mystnb]

looking for now-outdated files... none found
pickling environment... done
checking consistency... /Users/kpl/repos/project.lecture-mojo/README.md: WARNING: document isn't included in any toctree
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb: WARNING: document isn't included in any toctree
done
preparing documents... WARNING: unsupported theme option 'dark_logo' given
done
writing output... [100%] tutorial/mojo_demo                                     
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:22: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:32: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:109: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:125: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:140: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:151: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/shortest_paths.md:170: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:21: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:33: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:76: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:96: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:141: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:185: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/applications/wealth_distribution.md:207: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb:10002: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/examples/matmul_comparison.ipynb:20002: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:29: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:54: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:66: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:89: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:108: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:120: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:150: WARNING: Pygments lexer name 'mojo' is not known
/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md:163: WARNING: Pygments lexer name 'mojo' is not known
generating indices... genindex done
writing additional pages... search done
copying static files... done
copying extra files... done
dumping search index in English (code: en)... done
dumping object inventory... done
[etoc] missing index.html written as redirect to 'intro.html'
build succeeded, 27 warnings.

The HTML pages are in _build/html.

===============================================================================

Finished generating HTML for book.
Your book's HTML pages are here:
    _build/html/
You can look at your book by opening this file in a browser:
    _build/html/index.html
Or paste this line directly into your browser bar:
    file:///Users/kpl/repos/project.lecture-mojo/_build/html/index.html            

===============================================================================

% mojo -v
mojo 0.6.1 (876ded2e)

[kp992]

[ErrorLog] Failed to parse the module
[ErrorLog] Expression [3]:3:5: expression must be mutable for in-place operator destination
    x += 1
    ^

/Users/kpl/repos/project.lecture-mojo/tutorial/mojo_demo.md: Executed

This is one error log which is expected(tagged with raises-exception) and comes from

project.lecture-mojo/tutorial/mojo_demo.md

Line 71 in 7d7c9db

x += 1

[kp992]

Rest all is working fine for me locally. The generated pages locally also have the output.

[mmcky]

thanks @kp992