Group:
procedure and type-valued variables
Topic:
binding names to variables or expressions
Topic:
binding of names to objects
Topic:
macros
Topic:
named constants and expressions
Topic:
names as place holders
Topic:
parameters as argument place holders
Topic:
parameter passing by reference
Topic:
procedure valued variables
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Summary
In parameter passing by expression, or 'call by name', each parameter is replaced by the corresponding argument's text or literal expression. Since the text is re-evaluated each time the parameter is referenced, passing by expression is the same as passing a function. This mode is expensive to implement and has many unexpected side effects due to embedding an expression into one environment from another. For variables, parameter passing by name is equivalent to parameter passing by reference. (cbb 5/80)
Jensen's device uses call-by-name to get procedures for nested summations. Macro calls typically use call by name. (cbb 1/90)
Subtopic: usefulness of call-by-name 
| Quote: should not emphasize security; it disallows useful features such as call-by-name [»dahlOJ_1967]
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Subtopic: call-by-name as a procedure argument
| Quote: a call-by-name is passing a procedure [»bekiH_1971, OK]
| | Quote: in call-by-name, arguments are evaluated only when needed; i.e., on insertion into replacement text [»browPJ_1969]
| | Quote: in call-by-expression, substitute expression for each occurrence of parameter [»ledgHF9_1971, OK]
| | Quote: call-by-value if evaluate arguments before function, call-by-name if evaluate on each reference; use left-to-right evaluation to support extensions under call-by-value [»reynJC8_1972]
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Subtopic: call-by-name as constants
| Quote: a constant denotation as an argument is same as call-by-name; not evaluated until applied [»demeA3_1979]
| | QuoteRef: kostCH_1974 ;;370 parameters passed by name or reference .
| | QuoteRef: franN8_1977 ;;605 differentiate between value and name keyword parameters by call P (name-key = arg1... value-key:=arg2)
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Subtopic: call-by-name as virtual access
| Quote: a class may define virtual quantities for access from a super class; like call-by-name; compiler could check virtual specification [»dahlOJ_1967]
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Subtopic: Jensen's device
| Quote: Jensen's device uses pass-by-name for both index and indexed quantity; e.g., allows nested summations [»maclBJ_1987]
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Subtopic: problems with call by name
Quote: use call by value instead of call by name; call by name needs the dynamic scope of the actual parameter
[»dahlOJ_1967]
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Related Topics
Group: procedure and type-valued variables (4 topics, 95 quotes)
Topic: binding names to variables or expressions (10 items)
Topic: binding of names to objects (19 items)
Topic: macros (22 items)
Topic: named constants and expressions (21 items)
Topic: names as place holders (4 items)
Topic: parameters as argument place holders (15 items)
Topic: parameter passing by reference (11 items)
Topic: procedure valued variables
(34 items)
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