<br><br>On Tue, Aug 14, 2012 at 8:12 AM, Juan Vuletich (mail lists) <<a href="mailto:juanlists@jvuletich.org" target="_blank">juanlists@jvuletich.org</a>> wrote:<br>> WRT #'_value' precedence, it answers 2 if allowUnderscoreSelectors is false.<br>
> The question is actually meaningless in this case, as #'_value' is not a<br>> valid selector... If you set the preference to true, it correctly answers 1.<br><br>The preference controls the behaviour of the scanner. That is, it controls whether 'a_b' in scanned as 1 token or 3 tokens. It should have no effect on precedence. Consider the case where you set #allowUnderscoreSelectors to true, load a package that contains them, then set the preference to false again. That's probably the common case; cf ConfigurationOfXtreams. Now you've got selectors containing underscores in the image, but the preference is set to false. Are those selectors invalid now? Is it meaningless to ask their precedence?<br>
<br>No, those messags continue to work fine, and reflective code may well encounter selectors with underscores in them. Consider the following code: <br><br> <font face="'courier new', monospace">Smalltalk allSentMessages select: [:ea | ea isSymbol and: [ea precedence = 2]]</font><br>
<div><font face="'courier new', monospace"><br></font></div><div><font face="arial, helvetica, sans-serif">Cuis will include #'_value' in the answer. Or how about this:</font></div>
<div><font face="arial, helvetica, sans-serif"><br></font></div><div><font face="'courier new', monospace"> doesNotUnderstand: aMessage</font></div><div><font face="'courier new', monospace"> aMessage selector precedence = 2 ifTrue:</font></div>
<div><font face="'courier new', monospace"> [Transcript show: 'Got an infix message!']</font></div><div><font face="arial, helvetica, sans-serif"><br>
</font></div><div><font face="arial, helvetica, sans-serif">That kind of code may not be common, but it should work.</font></div><div><font face="arial, helvetica, sans-serif"><br></font></div><div><font class="Apple-style-span" face="arial, helvetica, sans-serif">Thanks for pointing me to Cuis' implementation. Digging into the details exposed a bug in my inelegant implementation as well—I had thought that binary selectors could contain underscores, but that's not the case. That implies that a single underscore is a unary message, not binary. Off to fix my test cases.</font></div>
<div><font class="Apple-style-span" face="arial, helvetica, sans-serif"><br></font></div><div><font class="Apple-style-span" face="arial, helvetica, sans-serif">Colin</font></div><div><font face="arial, helvetica, sans-serif"><br>
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