Pollen won’t stop you from calling a function that returns an incompatible value, like <spanclass="RktSym"><ahref="http://docs.racket-lang.org/plot/plotting.html#%28def._%28%28lib._plot%2Fmain..rkt%29._plot%29%29"class="RktValLink"data-pltdoc="x">plot</a></span>, which returns a bitmap image:</p><divclass="fileblock"><divclass="SIntrapara"><divclass="fileblock_filetitle"><spanclass="fileblock_filename"><spanclass="stt">"article.html.pm"</span></span></div></div><divclass="SIntrapara"><divclass="fileblock_filecontent"><divclass="SIntrapara"><blockquoteclass="SCodeFlow"><tablecellspacing="0"cellpadding="0"class="RktBlk"><tr><td><spanclass="RktMeta">#lang</span><spanclass="hspace"> </span><spanclass="RktMeta"></span><ahref="index.html"class="RktModLink"data-pltdoc="x"><spanclass="RktSym">pollen</span></a><spanclass="RktMeta"></span></td></tr><tr><td><spanclass="RktMeta"> </span></td></tr><tr><td><spanclass="RktMeta">◊</span><spanclass="RktPn">(</span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/reference/require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29"class="RktStxLink"data-pltdoc="x">require</a></span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktSym">math</span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/plot/plotting.html#%28def._%28%28lib._plot%2Fmain..rkt%29._plot%29%29"class="RktValLink"data-pltdoc="x">plot</a></span><spanclass="RktPn">)</span><spanclass="RktMeta"></span></td></tr><tr><td><spanclass="RktMeta"> </span></td></tr><tr><td><spanclass="RktMeta">Here</span><spanclass="RktVal">'</span><spanclass="RktMeta">s</span><spanclass="hspace"> </span><spanclass="RktMeta">a</span><spanclass="hspace"> </span><spanclass="RktMeta">sine</span><spanclass="hspace"> </span><spanclass="RktMeta">wave:</span></td></tr><tr><td><spanclass="RktMeta">◊</span><spanclass="RktPn">(</span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/plot/plotting.html#%28def._%28%28lib._plot%2Fmain..rkt%29._plot%29%29"class="RktValLink"data-pltdoc="x">plot</a></span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktPn">(</span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/plot/renderer2d.html#%28def._%28%28lib._plot%2Fmain..rkt%29._function%29%29"class="RktValLink"data-pltdoc="x">function</a></span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/reference/generic-numbers.html#%28def._%28%28quote._~23~25kernel%29._sin%29%29"class="RktValLink"data-pltdoc="x">sin</a></span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktPn">(</span><spanclass="RktSym"><ahref="http://docs.racket-lang.org/reference/generic-numbers.html#%28def._%28%28quote._~23~25kernel%29._-%29%29"class="RktValLink"data-pltdoc="x"><spanclass="nobreak">-</span></a></span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktSym">pi</span><spanclass="RktPn">)</span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktSym">pi</span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktPn">#:label</span><spanclass="RktMeta"></span><spanclass="hspace"> </span><spanclass="RktMeta"></span><spanclass="RktVal">"y</span><spanclass="hspace"> </span><spanclass="RktVal">=</span><spanclass="hspace"> </span><spanclass="RktVal">sin(x)"</span><spanclass="RktPn">)</span><spanclass="RktPn">)</span><spanclass="RktMeta"></span></td></tr></table></blockquote></div></div></div></div><p>But it won’t work when you try to run it in DrRacket or load it in the project server.
2-4 three source files
5 pagetree
6 template
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