Huangzj
54 lines
1.7 KiB
Go
54 lines
1.7 KiB
Go
package linq
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// Aggregate applies an accumulator function over a sequence.
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//
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// Aggregate method makes it simple to perform a calculation over a sequence of values.
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// This method works by calling f() one time for each element in source
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// except the first one. Each time f() is called, Aggregate passes both
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// the element from the sequence and an aggregated value (as the first argument to f()).
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// The first element of source is used as the initial aggregate value.
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// The result of f() replaces the previous aggregated value.
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//
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// Aggregate returns the final result of f().
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func (q Query) Aggregate(
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f func(interface{}, interface{}) interface{}) interface{} {
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next := q.Iterate()
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result, any := next()
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if !any {
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return nil
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}
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for current, ok := next(); ok; current, ok = next() {
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result = f(result, current)
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}
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return result
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}
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// AggregateWithSeed applies an accumulator function over a sequence.
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// The specified seed value is used as the initial accumulator value.
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//
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// Aggregate method makes it simple to perform a calculation over a sequence of values.
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// This method works by calling f() one time for each element in source
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// except the first one. Each time f() is called, Aggregate passes both
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// the element from the sequence and an aggregated value (as the first argument to f()).
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// The value of the seed parameter is used as the initial aggregate value.
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// The result of f() replaces the previous aggregated value.
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//
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// Aggregate returns the final result of f().
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func (q Query) AggregateWithSeed(
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seed interface{},
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f func(interface{}, interface{}) interface{},
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) interface{} {
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next := q.Iterate()
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result := seed
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for current, ok := next(); ok; current, ok = next() {
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result = f(result, current)
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}
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return result
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}
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