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@@ 25,7 +25,7 @@ With `\showExplanation{always}` the author can define, that an explanations is a 
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The optional condition is an expression that can be evaluated to true of false. It can contain 
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* logical operators: AND, OR, NOT 
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* relation symbols: =, !=, >, >=, <, <= 

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+* relation symbols: =, !=, >, >=, <, <= (make sure to have a white space before and after a relation symbol, e.g. type `z != 0` instead of `z!=0`) 
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* variable references 
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* answer references: An answer reference can be 'ans', referencing the current answer (on answer level only) or 'ans_index' to reference the answer with the specific index, e.g. 'ans_3'. [Example in WebMiau](https://miau.mumie.net/webmiau/editor/content%2Fexamples%2Fexplanations%2Fprb_differentiated_feedback_1.src.tex) 
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* functions: length, count, valid, equal, equalString, equalTrimmedString, equalChoice, edited, condition, equalAnswer 
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