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languages, but I miss them in the C++. I' m taking the inspiration from languages
like Rust (all that we will implement) or Kotlin (< code > TODO< / code > ) that have them
implemented.< / p >
< p > You may ask what placeholders do we need in the code, in our case we will be
talking about TODOs and unexpected situations, such as not implemented branches.< / p >
< p > Namely we will implement< / p >
< ul >
< li > < code > todo< / code > ,< / li >
< li > < code > unimplemented< / code > , and< / li >
< li > < code > unreachable< / code > .< / li >
< / ul >
< h2 class = "anchor anchorWithStickyNavbar_LWe7" id = "design" > Design< a href = "#design" class = "hash-link" aria-label = "Direct link to Design" title = "Direct link to Design" > < / a > < / h2 >
< p > If we take the two languages mentioned above as examples, there are at least two
ways how to implement them:< / p >
< ol >
< li > < em > panic< / em > when they are reached (as they do in Rust), or< / li >
< li > < em > raise< / em > an exception when they are reached (as they do in Kotlin).< / li >
< / ol >
< p > I will choose raising an exception, since the closest equivalent of < em > panic< / em > in
C++ would be < code > assert< / code > s that are (by default) disabled in the < em > release builds< / em > .< / p >
< p > However I am too lazy to do:< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token keyword" style = "color:#00009f" > throw< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token comment" style = "color:#999988;font-style:italic" > // or< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > throw< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token string" style = "color:#e3116c" > " optional note" < / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < br > < / span > < / code > < / pre > < div class = "buttonGroup__atx" > < button type = "button" aria-label = "Copy code to clipboard" title = "Copy" class = "clean-btn" > < span class = "copyButtonIcons_eSgA" aria-hidden = "true" > < svg viewBox = "0 0 24 24" class = "copyButtonIcon_y97N" > < path fill = "currentColor" d = "M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z" > < / path > < / svg > < svg viewBox = "0 0 24 24" class = "copyButtonSuccessIcon_LjdS" > < path fill = "currentColor" d = "M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z" > < / path > < / svg > < / span > < / button > < / div > < / div > < / div >
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< p > Therefore we will implement exceptions and also wrap them in functions, so that
we can do:< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token comment" style = "color:#999988;font-style:italic" > // or< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token string" style = "color:#e3116c" > " optional note" < / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < br > < / span > < / code > < / pre > < div class = "buttonGroup__atx" > < button type = "button" aria-label = "Copy code to clipboard" title = "Copy" class = "clean-btn" > < span class = "copyButtonIcons_eSgA" aria-hidden = "true" > < svg viewBox = "0 0 24 24" class = "copyButtonIcon_y97N" > < path fill = "currentColor" d = "M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z" > < / path > < / svg > < svg viewBox = "0 0 24 24" class = "copyButtonSuccessIcon_LjdS" > < path fill = "currentColor" d = "M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z" > < / path > < / svg > < / span > < / button > < / div > < / div > < / div >
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< div class = "theme-admonition theme-admonition-tip admonition_xJq3 alert alert--success" > < div class = "admonitionHeading_Gvgb" > < span class = "admonitionIcon_Rf37" > < svg viewBox = "0 0 12 16" > < path fill-rule = "evenodd" d = "M6.5 0C3.48 0 1 2.19 1 5c0 .92.55 2.25 1 3 1.34 2.25 1.78 2.78 2 4v1h5v-1c.22-1.22.66-1.75 2-4 .45-.75 1-2.08 1-3 0-2.81-2.48-5-5.5-5zm3.64 7.48c-.25.44-.47.8-.67 1.11-.86 1.41-1.25 2.06-1.45 3.23-.02.05-.02.11-.02.17H5c0-.06 0-.13-.02-.17-.2-1.17-.59-1.83-1.45-3.23-.2-.31-.42-.67-.67-1.11C2.44 6.78 2 5.65 2 5c0-2.2 2.02-4 4.5-4 1.22 0 2.36.42 3.22 1.19C10.55 2.94 11 3.94 11 5c0 .66-.44 1.78-.86 2.48zM4 14h5c-.23 1.14-1.3 2-2.5 2s-2.27-.86-2.5-2z" > < / path > < / svg > < / span > tip< / div > < div class = "admonitionContent_BuS1" > < p > Wrapping them in a function (or macro) will allow us to do a little magic trick.< / p > < / div > < / div >
< h2 class = "anchor anchorWithStickyNavbar_LWe7" id = "implementation" > Implementation< a href = "#implementation" class = "hash-link" aria-label = "Direct link to Implementation" title = "Direct link to Implementation" > < / a > < / h2 >
< p > We' re going to utilize the exceptions, so we' ll need to include the < code > exception< / code >
header and we will start with a simple < code > _todo< / code > exception class.< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < exception> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < string> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > class< / span > < span class = "token plain" > < / span > < span class = "token class-name" > _todo< / span > < span class = "token plain" > < / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < span class = "token base-clause keyword" style = "color:#00009f" > public< / span > < span class = "token base-clause" > std< / span > < span class = "token base-clause double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token base-clause class-name" > exception< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > std< / span > < span class = "token double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token plain" > string cause< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > public< / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > cause< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token string" style = "color:#e3116c" > " not yet implemented" < / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token punctuation" style = "color:#393A34" > }< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token plain" > std< / span > < span class = "token double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token plain" > string< / span > < span class = "token operator" style = "color:#393A34" > & & < / span > < span class = "token plain" > excuse< / span > < span class = "toke
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< p > In this case we have 2 constructors:< / p >
< ol >
< li > default constructor without any parameters that will return just
< code > not yet implemented< / code > < / li >
< li > and one parametrized with an “excuse” that will return string like:
< code > not yet implemented: ‹ › < / code > < / li >
< / ol >
< p > If we were to use it now, we would need to do something like:< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > " placeholders.hpp" < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > int< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > main< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > throw< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > return< / span > < span class = "token plain" > < / span > < span class = "token number" style = "color:#36acaa" > 0< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > }< / span > < br > < / span > < / code > < / pre > < div class = "buttonGroup__atx" > < button type = "button" aria-label = "Copy code to clipboard" title = "Copy" class = "clean-btn" > < span class = "copyButtonIcons_eSgA" aria-hidden = "true" > < svg viewBox = "0 0 24 24" class = "copyButtonIcon_y97N" > < path fill = "currentColor" d = "M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z" > < / path > < / svg > < svg viewBox = "0 0 24 24" class = "copyButtonSuccessIcon_LjdS" > < path fill = "currentColor" d = "M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z" > < / path > < / svg > < / span > < / button > < / div > < / div > < / div >
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< h2 class = "anchor anchorWithStickyNavbar_LWe7" id = "wrapping-in-a-function" > Wrapping in a function< a href = "#wrapping-in-a-function" class = "hash-link" aria-label = "Direct link to Wrapping in a function" title = "Direct link to Wrapping in a function" > < / a > < / h2 >
< p > I am a lazy person, so we will wrap the exception in a function that will throw
it:< / p >
2023-11-25 21:52:07 +01:00
< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token keyword" style = "color:#00009f" > void< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > throw< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > }< / span > < br > < / span > < / code > < / pre > < div class = "buttonGroup__atx" > < button type = "button" aria-label = "Copy code to clipboard" title = "Copy" class = "clean-btn" > < span class = "copyButtonIcons_eSgA" aria-hidden = "true" > < svg viewBox = "0 0 24 24" class = "copyButtonIcon_y97N" > < path fill = "currentColor" d = "M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z" > < / path > < / svg > < svg viewBox = "0 0 24 24" class = "copyButtonSuccessIcon_LjdS" > < path fill = "currentColor" d = "M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z" > < / path > < / svg > < / span > < / button > < / div > < / div > < / div >
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< p > This can be used like:< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > " placeholders.hpp" < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > int< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > main< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > return< / span > < span class = "token plain" > < / span > < span class = "token number" style = "color:#36acaa" > 0< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > }< / span > < br > < / span > < / code > < / pre > < div class = "buttonGroup__atx" > < button type = "button" aria-label = "Copy code to clipboard" title = "Copy" class = "clean-btn" > < span class = "copyButtonIcons_eSgA" aria-hidden = "true" > < svg viewBox = "0 0 24 24" class = "copyButtonIcon_y97N" > < path fill = "currentColor" d = "M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z" > < / path > < / svg > < svg viewBox = "0 0 24 24" class = "copyButtonSuccessIcon_LjdS" > < path fill = "currentColor" d = "M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z" > < / path > < / svg > < / span > < / button > < / div > < / div > < / div >
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< h2 class = "anchor anchorWithStickyNavbar_LWe7" id = "magic-trick" > Magic trick< a href = "#magic-trick" class = "hash-link" aria-label = "Direct link to Magic trick" title = "Direct link to Magic trick" > < / a > < / h2 >
< p > At the beginning I' ve mentioned that by wrapping the exceptions in a helper
functions that will throw them, we can do a nice magic trick <!-- --> 😄<!-- --> This trick
will consist of formatted string and for that we will use
< a href = "https://en.cppreference.com/w/cpp/utility/format/format" target = "_blank" rel = "noopener noreferrer" > < code > std::format< / code > < / a > that is
available since C++20.< / p >
< p > We just need to add one more overload for our < code > todo()< / code > :< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < format> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > template< / span > < span class = "token operator" style = "color:#393A34" > < < / span > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > class< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token plain" > Args < / span > < span class = "token operator" style = "color:#393A34" > > < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > void< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token plain" > std< / span > < span class = "token double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token plain" > format_string< / span > < span class = "token operator" style = "color:#393A34" > < < / span > < span class = "token plain" > Args< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token operator" style = "color:#393A34" > > < / span > < span class = "token plain" > fmt< / span > < span class = "token punctuation" style = "color:#393A34" > ,< / span > < span class = "token plain" > Args< / span > < span class = "token operator" style = "color:#393A34" > & & < / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token plain" > args< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > throw< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token plain" > std< / span > < span class = "token double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token function" style = "color:#d73a49" > format< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token plain" > fmt< / span > < span class = "token punctuation" style = "color:#393A34" > ,< / span > < span class = "token plain" > args< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > .< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < /
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< h2 class = "anchor anchorWithStickyNavbar_LWe7" id = "finishing-off-with-2-more-exceptions" > Finishing off with 2 more exceptions< a href = "#finishing-off-with-2-more-exceptions" class = "hash-link" aria-label = "Direct link to Finishing off with 2 more exceptions" title = "Direct link to Finishing off with 2 more exceptions" > < / a > < / h2 >
< p > Now we can repeat the same process for the other two exceptions I' ve mentioned< / p >
< ul >
< li > < code > unimplemented< / code > , and< / li >
< li > < code > unreachable< / code > .< / li >
< / ul >
< p > In the end we should end up with something like this:< / p >
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< div class = "language-cpp codeBlockContainer_Ckt0 theme-code-block" style = "--prism-color:#393A34;--prism-background-color:#f6f8fa" > < div class = "codeBlockContent_biex" > < pre tabindex = "0" class = "prism-code language-cpp codeBlock_bY9V thin-scrollbar" style = "color:#393A34;background-color:#f6f8fa" > < code class = "codeBlockLines_e6Vv" > < span class = "token-line" style = "color:#393A34" > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < exception> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < format> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token macro property directive-hash" style = "color:#36acaa" > #< / span > < span class = "token macro property directive keyword" style = "color:#00009f" > include< / span > < span class = "token macro property" style = "color:#36acaa" > < / span > < span class = "token macro property string" style = "color:#e3116c" > < string> < / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > class< / span > < span class = "token plain" > < / span > < span class = "token class-name" > _todo< / span > < span class = "token plain" > < / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < span class = "token base-clause keyword" style = "color:#00009f" > public< / span > < span class = "token base-clause" > std< / span > < span class = "token base-clause double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token base-clause class-name" > exception< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > std< / span > < span class = "token double-colon punctuation" style = "color:#393A34" > ::< / span > < span class = "token plain" > string cause< / span > < span class = "token punctuation" style = "color:#393A34" > ;< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" style = "display:inline-block" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token keyword" style = "color:#00009f" > public< / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393A34" > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > _todo< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token operator" style = "color:#393A34" > :< / span > < span class = "token plain" > < / span > < span class = "token function" style = "color:#d73a49" > cause< / span > < span class = "token punctuation" style = "color:#393A34" > (< / span > < span class = "token string" style = "color:#e3116c" > " not yet implemented" < / span > < span class = "token punctuation" style = "color:#393A34" > )< / span > < span class = "token plain" > < / span > < span class = "token punctuation" style = "color:#393A34" > {< / span > < span class = "token punctuation" style = "color:#393A34" > }< / span > < span class = "token plain" > < / span > < br > < / span > < span class = "token-line" style = "color:#393
2023-11-24 18:33:21 +01:00
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