Topic:
replacement as moving information
Topic:
variable as reference to a value
Topic:
variable as reference to storage
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Summary
The left hand side of a replacement denotes a reference to a variable. The right hand side denotes a value. After the replacement, the left hand side refers to a value equivalent to the right hand side. The left hand's physical reference is a literal; it does not change. The right hand's value is logical which only needs to match the value referenced by the left hand side. (cbb 5/80)
Subtopic: transfering value 
| QuoteRef: reynJC5_1970 ;;313 r := v is to cause the reference denoted by r to possess the value denoted by v "
| | Quote: after an assignment, the value denoted by the variable is the same as the value from the expression [»hoarCA8_1978]
| | QuoteRef: goldA3_1976 ;;9 "To hand an object d the meaning '3' in Smalltalk, we say: .hand. d<-3!" .hand. indicates literal name follows, ! says do it
| | QuoteRef: hehnEC7_1975 ;;20 assignment by name .larrow. value where type matches
| | QuoteRef: richM_1974 ;;13 lmode gets lvalue (address) and rmode gets rvalue eg e1 := e2 generate new object with lmode value of e1 and rmode value of e2
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Subtopic: copy vs. reference
| Quote: in CLU, an assignment causes sharing; after 'x:=y' both x and y refer to the same object [»liskB_1996]
| | Quote: a copy constructor creates a copy; zapping a value does not change other initializations [»dehnJC4_1998]
| | Quote: Modula-3 objects are assigned by reference; to copy an object, copy its fields [»cardL_1991]
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Subtopic: variable as value
| Quote: a variable denotes a fixed address whose content is its value [»straC3_1973]
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Subtopic: assignment vs initialization
Quote: assignment and initialization are different operations; assignment only applies to properly constructed objects
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Related Topics
Topic: replacement as moving information (4 items)
Topic: variable as reference to a value (21 items)
Topic: variable as reference to storage
(12 items)
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