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Revision as of 15:51, 25 March 2021

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→‎{{header|Phix}}: added syntax colouring the hard way, phix/basics
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m (→‎{{header|Phix}}: added syntax colouring the hard way, phix/basics)
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=={{header|Phix}}==
{{libheader|Phix/basics}}
<lang Phix>constant word = "the", -- (also try this with "th"/"he")
<!--<lang Phix>-->
sentence = "the last thing the man said was the"
<span style="color: #008080;">constant</span> <span style="color: #000000;">word</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"the"</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- (also try this with "th"/"he")</span>
-- sentence = "thelastthingthemansaidwasthe" -- (practically the same results)▼
<span style="color: #000000;">sentence</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"the last thing the man said was the"</span>
 
▲ <span style="color: #000080;font-style:italic;">-- sentence = "thelastthingthemansaidwasthe" -- (practically the same results)
-- A common, but potentially inefficient idiom for checking for a substring at the start is:▼
if match(word,sentence)=1 then
▲ -- A common, but potentially inefficient idiom for checking for a substring at the start is:</span>
?"yes(1)"
<span style="color: #008080;">if</span> <span style="color: #7060A8;">match</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
end if
<span style="color: #0000FF;">?</span><span style="color: #008000;">"yes(1)"</span>
-- A more efficient method is to test the appropriate slice▼
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if length(sentence)>=length(word)
▲ <span style="color: #000080;font-style:italic;">-- A more efficient method is to test the appropriate slice</span>
and sentence[1..length(word)]=word then
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)>=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)</span>
?"yes(2)"
<span style="color: #008080;">and</span> <span style="color: #000000;">sentence</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">..</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)]=</span><span style="color: #000000;">word</span> <span style="color: #008080;">then</span>
end if
<span style="color: #0000FF;">?</span><span style="color: #008000;">"yes(2)"</span>
-- Which is almost identical to checking for a word at the end▼
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if length(sentence)>=length(word)
▲ <span style="color: #000080;font-style:italic;">-- Which is almost identical to checking for a word at the end</span>
and sentence[-length(word)..-1]=word then
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)>=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)</span>
?"yes(3)"
<span style="color: #008080;">and</span> <span style="color: #000000;">sentence</span><span style="color: #0000FF;">[-</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)..-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">word</span> <span style="color: #008080;">then</span>
end if
<span style="color: #0000FF;">?</span><span style="color: #008000;">"yes(3)"</span>
-- Or sometimes you will see this, a tiny bit more efficient:▼
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
if length(sentence)>=length(word)
▲ <span style="color: #000080;font-style:italic;">-- Or sometimes you will see this, a tiny bit more efficient:</span>
and match(word,sentence,length(sentence)-length(word)+1) then
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)>=</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)</span>
?"yes(4)"
<span style="color: #008080;">and</span> <span style="color: #7060A8;">match</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)-</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">)+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
end if
<span style="color: #0000FF;">?</span><span style="color: #008000;">"yes(4)"</span>
-- Finding all occurences is a snap:
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
integer r = match(word,sentence)
<span style="color: #000080;font-style:italic;">-- Finding all occurences is a snap:</span>
while r!=0 do
<span style="color: #004080;">integer</span> <span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">match</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)</span>
?r
<span style="color: #008080;">while</span> <span style="color: #000000;">r</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">do</span>
r = match(word,sentence,r+1)
<span style="color: #0000FF;">?</span><span style="color: #000000;">r</span>
end while</lang>
<span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">match</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">,</span><span style="color: #000000;">r</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #000080;font-style:italic;">-- or equivalently:</span>
<span style="color: #0000FF;">?</span><span style="color: #7060A8;">match_all</span><span style="color: #0000FF;">(</span><span style="color: #000000;">word</span><span style="color: #0000FF;">,</span><span style="color: #000000;">sentence</span><span style="color: #0000FF;">)</span>
<!--</lang>-->
{{out}}
<pre>
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{1,16,33}
</pre>
 
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