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History variables (view source)

Revision as of 14:07, 19 January 2022

6,251 bytes added ,  2 years ago
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→‎{{header|Phix}}: added syntax colouring, marked p2js compatible
m (→‎{{header|Phix}}: added syntax colouring, marked p2js compatible)
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=={{header|Phix}}==
No native support, but trivial to implement.<br>
If you only need the history for a single variable, you can just do this, though it does not work under pwa/p2js:
<!--<lang Phix>sequence history = {}-->
<span style="color: #008080;">without</span> <span style="color: #008080;">js</span> <span style="color: #000080;font-style:italic;">-- (desktop/Phix only)</span>
 
<span style="color: #004080;">sequence</span> <span style="color: #000000;">history</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
type hvt(object o)
history = append(history,o)
<span style="color: #008080;">type</span> <span style="color: #000000;">hvt</span><span style="color: #0000FF;">(</span><span style="color: #004080;">object</span> <span style="color: #000000;">o</span><span style="color: #0000FF;">)</span>
return true
<span style="color: #000000;">history</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">history</span><span style="color: #0000FF;">,</span><span style="color: #000000;">o</span><span style="color: #0000FF;">)</span>
end type
<span style="color: #008080;">return</span> <span style="color: #004600;">true</span>
 
<span style="color: #008080;">end</span> <span style="color: #008080;">type</span>
hvt test = 1
test = 2
<span style="color: #000000;">hvt</span> <span style="color: #000000;">test</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
test = 3
<span style="color: #000000;">test</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">2</span>
?{"current",test}
<span style="color: #000000;">test</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">3</span>
?{"history",history}</lang>
<span style="color: #0000FF;">?{</span><span style="color: #008000;">"current"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">test</span><span style="color: #0000FF;">}</span>
<span style="color: #0000FF;">?{</span><span style="color: #008000;">"history"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">history</span><span style="color: #0000FF;">}</span>
<!--</lang>-->
{{out}}
<pre>
Line 2,147 ⟶ 2,150:
{"history",{1,2,3}}
</pre>
Multiple history variables would require that routines must be invoked to create, update, and inspect them, and would be pwa/p2js compatible.<br>
Writing this as a separate reusable component (but omitting destroy/freelist handling for simplicity):
<!--<lang Phix>(phixonline)-- history.e>
<span style="color: #000080;font-style:italic;">-- history.e</span>
sequence histories = {}
<span style="color: #004080;">sequence</span> <span style="color: #000000;">histories</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
 
global function new_history_id(object v)
<span style="color: #008080;">global</span> <span style="color: #008080;">function</span> <span style="color: #000000;">new_history_id</span><span style="color: #0000FF;">(</span><span style="color: #004080;">object</span> <span style="color: #000000;">v</span><span style="color: #0000FF;">)</span>
histories = append(histories,{v})
<span style="color: #000000;">histories</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">histories</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">v</span><span style="color: #0000FF;">})</span>
return length(histories)
<span style="color: #008080;">return</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">histories</span><span style="color: #0000FF;">)</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
 
global procedure set_hv(integer hv, object v)
<span style="color: #008080;">global</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">set_hv</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">hv</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">object</span> <span style="color: #000000;">v</span><span style="color: #0000FF;">)</span>
histories[hv] = append(histories[hv],v)
<span style="color: #000000;">histories</span><span style="color: #0000FF;">[</span><span style="color: #000000;">hv</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">histories</span><span style="color: #0000FF;">[</span><span style="color: #000000;">hv</span><span style="color: #0000FF;">],</span><span style="color: #000000;">v</span><span style="color: #0000FF;">)</span>
end procedure
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
 
global function get_hv(integer hv)
<span style="color: #008080;">global</span> <span style="color: #008080;">function</span> <span style="color: #000000;">get_hv</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">hv</span><span style="color: #0000FF;">)</span>
return histories[hv][$]
<span style="color: #008080;">return</span> <span style="color: #000000;">histories</span><span style="color: #0000FF;">[</span><span style="color: #000000;">hv</span><span style="color: #0000FF;">][$]</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
 
global function get_hv_full_history(integer hv)
<span style="color: #008080;">global</span> <span style="color: #008080;">function</span> <span style="color: #000000;">get_hv_full_history</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">hv</span><span style="color: #0000FF;">)</span>
return histories[hv]
<span style="color: #008080;">return</span> <span style="color: #000000;">histories</span><span style="color: #0000FF;">[</span><span style="color: #000000;">hv</span><span style="color: #0000FF;">]</span>
end function</lang>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<!--</lang>-->
And use it like this
<!--<lang Phix>include history.e(phixonline)-->
<span style="color: #008080;">include</span> <span style="color: #000000;">history</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span>
 
constant test2 = new_history_id(1)
<span style="color: #008080;">constant</span> <span style="color: #000000;">test2</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">new_history_id</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span>
set_hv(test2, 2)
<span style="color: #000000;">set_hv</span><span style="color: #0000FF;">(</span><span style="color: #000000;">test2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">2</span><span style="color: #0000FF;">)</span>
set_hv(test2, 3)
<span style="color: #000000;">set_hv</span><span style="color: #0000FF;">(</span><span style="color: #000000;">test2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">3</span><span style="color: #0000FF;">)</span>
?{"current",get_hv(test2)}
<span style="color: #0000FF;">?{</span><span style="color: #008000;">"current"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">get_hv</span><span style="color: #0000FF;">(</span><span style="color: #000000;">test2</span><span style="color: #0000FF;">)}</span>
?{"history",get_hv_full_history(test2)}</lang>
<span style="color: #0000FF;">?{</span><span style="color: #008000;">"history"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">get_hv_full_history</span><span style="color: #0000FF;">(</span><span style="color: #000000;">test2</span><span style="color: #0000FF;">)}</span>
<!--</lang>-->
Same output. Of course test2 does not ''have'' to be a constant, but it may help.
 
Petelomax
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