<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">Given the following extension ...</p><pre class="lang-swift prettyprinted prettyprint" style="margin-top: 0px; margin-bottom: 1em; padding: 5px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-size: 13px; line-height: inherit; vertical-align: baseline; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; white-space: inherit;" class=""><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">extension</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">{</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">typealias</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Triple</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">=</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">static</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">let</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> pythagoreanTriple</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">:</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Triple</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">=</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">3</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">4</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">5</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">}</span></code></pre><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">... why does Swift compiler emits the following errors?</p><pre class="lang-swift prettyprinted prettyprint" style="margin-top: 0px; margin-bottom: 1em; padding: 5px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-size: 13px; line-height: inherit; vertical-align: baseline; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; white-space: inherit;" class=""><span class="com" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(133, 140, 147);">// Type of expression is ambiguous without more context
</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">let</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> a</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">:</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">=</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">pythagoreanTriple</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">.</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">0</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
</span><span class="com" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(133, 140, 147);">// Type of expression is ambiguous without more context
</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">func</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> f</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(_</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> x</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">:</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(43, 145, 175);">Double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">{}</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
f</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">pythagoreanTriple</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">.</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">0</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span></code></pre><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">The errors disappear with explicit <code style="margin: 0px; padding: 1px 5px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-size: 13px; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; background-color: rgb(239, 240, 241); white-space: pre-wrap;" class="">Double.pythagoreanTriple.0</code>.</p><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">Why doesn't the compiler infer <code style="margin: 0px; padding: 1px 5px; border: 0px; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, sans-serif; font-size: 13px; font-style: inherit; font-variant-caps: inherit; line-height: inherit; vertical-align: baseline; background-color: rgb(239, 240, 241); white-space: pre-wrap;" class="">Double</code> in this case?</p><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">FYI: Posted also to Stack Overflow here:</p><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class=""><a href="https://stackoverflow.com/questions/45998034/type-of-expression-is-ambiguous-for-static-tuples" class="">https://stackoverflow.com/questions/45998034/type-of-expression-is-ambiguous-for-static-tuples</a></p><p style="margin: 0px 0px 1em; padding: 0px; border: 0px; font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif; font-size: 15px; line-height: inherit; vertical-align: baseline; clear: both; color: rgb(36, 39, 41);" class="">R+</p></body></html>