How do I use strstr in Swift to search for a string within a string?

How do I use strstr in Swift to search for a string within a string? I'm not sure how to use UnsafePointer! in Swift. strstr takes two arguments of both that type and returns a value of that type. Is this C or C++? Can I use C or C++ code in Swift, or could I use strstr in Objective-C and use a bridging header?

When I use this code:

var str1 = "Hello"

var str2 = "ll"



var ptr = strstr(str1, str2)



print(ptr)

print(ptr?.pointee)

I get this result:

Optional(0x00006000039bd762)

Optional(0)

asked Nov 23 '18 at 17:43

Daniel Brower

10510

6

Why would you want to do that? There is str1.range(of: str2) in Swift.

– Martin R
Nov 23 '18 at 17:51

1

I wonder if this is an XY problem. Do you really want to use strstr() or is your actual problem how to locate one Swift string within another Swift string?

– Martin R
Nov 23 '18 at 18:05

1

Then the title is misleading, and your question is for example answered here: stackoverflow.com/questions/32305891/….

– Martin R
Nov 23 '18 at 18:09

1

This is indeed an XY problem. If you don't know how to accomplish a task in a new language/OS, ask how to accomplish the task at a high level, not how you would accomplish a specific implementation. If we had simply asked the question you asked you would have gone down the wrong coding path.

– Duncan C
Nov 23 '18 at 18:50

2

The summary: "The XY problem is asking about your attempted solution rather than your actual problem. That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."

– Duncan C
Nov 24 '18 at 2:09

|
show 4 more comments

When I use this code:

var str1 = "Hello"

var str2 = "ll"



var ptr = strstr(str1, str2)



print(ptr)

print(ptr?.pointee)

I get this result:

Optional(0x00006000039bd762)

Optional(0)

asked Nov 23 '18 at 17:43

Daniel Brower

10510

6

Why would you want to do that? There is str1.range(of: str2) in Swift.

– Martin R
Nov 23 '18 at 17:51

1

I wonder if this is an XY problem. Do you really want to use strstr() or is your actual problem how to locate one Swift string within another Swift string?

– Martin R
Nov 23 '18 at 18:05

1

Then the title is misleading, and your question is for example answered here: stackoverflow.com/questions/32305891/….

– Martin R
Nov 23 '18 at 18:09

1

This is indeed an XY problem. If you don't know how to accomplish a task in a new language/OS, ask how to accomplish the task at a high level, not how you would accomplish a specific implementation. If we had simply asked the question you asked you would have gone down the wrong coding path.

– Duncan C
Nov 23 '18 at 18:50

2

The summary: "The XY problem is asking about your attempted solution rather than your actual problem. That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."

– Duncan C
Nov 24 '18 at 2:09

|
show 4 more comments

When I use this code:

var str1 = "Hello"

var str2 = "ll"



var ptr = strstr(str1, str2)



print(ptr)

print(ptr?.pointee)

I get this result:

Optional(0x00006000039bd762)

Optional(0)

asked Nov 23 '18 at 17:43

Daniel Brower

10510

When I use this code:

var str1 = "Hello"

var str2 = "ll"



var ptr = strstr(str1, str2)



print(ptr)

print(ptr?.pointee)

I get this result:

Optional(0x00006000039bd762)

Optional(0)

swift strstr

asked Nov 23 '18 at 17:43

Daniel Brower

10510

asked Nov 23 '18 at 17:43

Daniel Brower

10510

asked Nov 23 '18 at 17:43

Daniel Brower

10510

asked Nov 23 '18 at 17:43

Daniel Brower

10510

asked Nov 23 '18 at 17:43

Daniel Brower

10510

6

Why would you want to do that? There is str1.range(of: str2) in Swift.

– Martin R
Nov 23 '18 at 17:51

1

I wonder if this is an XY problem. Do you really want to use strstr() or is your actual problem how to locate one Swift string within another Swift string?

– Martin R
Nov 23 '18 at 18:05

1

Then the title is misleading, and your question is for example answered here: stackoverflow.com/questions/32305891/….

– Martin R
Nov 23 '18 at 18:09

1

This is indeed an XY problem. If you don't know how to accomplish a task in a new language/OS, ask how to accomplish the task at a high level, not how you would accomplish a specific implementation. If we had simply asked the question you asked you would have gone down the wrong coding path.

– Duncan C
Nov 23 '18 at 18:50

2

The summary: "The XY problem is asking about your attempted solution rather than your actual problem. That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."

– Duncan C
Nov 24 '18 at 2:09

|
show 4 more comments

6

Why would you want to do that? There is str1.range(of: str2) in Swift.

– Martin R
Nov 23 '18 at 17:51

1

I wonder if this is an XY problem. Do you really want to use strstr() or is your actual problem how to locate one Swift string within another Swift string?

– Martin R
Nov 23 '18 at 18:05

1

Then the title is misleading, and your question is for example answered here: stackoverflow.com/questions/32305891/….

– Martin R
Nov 23 '18 at 18:09

1

This is indeed an XY problem. If you don't know how to accomplish a task in a new language/OS, ask how to accomplish the task at a high level, not how you would accomplish a specific implementation. If we had simply asked the question you asked you would have gone down the wrong coding path.

– Duncan C
Nov 23 '18 at 18:50

2

The summary: "The XY problem is asking about your attempted solution rather than your actual problem. That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."

– Duncan C
Nov 24 '18 at 2:09

Why would you want to do that? There is str1.range(of: str2) in Swift.

– Martin R
Nov 23 '18 at 17:51

I wonder if this is an XY problem. Do you really want to use strstr() or is your actual problem how to locate one Swift string within another Swift string?

– Martin R
Nov 23 '18 at 18:05

Then the title is misleading, and your question is for example answered here: stackoverflow.com/questions/32305891/….

– Martin R
Nov 23 '18 at 18:09

This is indeed an XY problem. If you don't know how to accomplish a task in a new language/OS, ask how to accomplish the task at a high level, not how you would accomplish a specific implementation. If we had simply asked the question you asked you would have gone down the wrong coding path.

– Duncan C
Nov 23 '18 at 18:50

The summary: "The XY problem is asking about your attempted solution rather than your actual problem. That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."

– Duncan C
Nov 24 '18 at 2:09

|
show 4 more comments

1 Answer
1

active

oldest

votes

Swift is a very powerful language. Try out some of its higher level features.
Try putting this in playground.

var word = "Hello"

print(String(format: "Word: %@", word))

let range = word.range(of: "ll")!

print(String(format: "Lower Bound: %d", range.lowerBound.encodedOffset))

print(String(format: "Upper Bound: %d", range.upperBound.encodedOffset))



word = word.replacingOccurrences(of: "ll", with: "")

print(String(format: "Word after replacement: %@", word))



for (i, c) in word.enumerated() {

    print(String(format: "Index: %d, Character: %@", i, String(c)))

}

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

add a comment |

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1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

Swift is a very powerful language. Try out some of its higher level features.
Try putting this in playground.

var word = "Hello"

print(String(format: "Word: %@", word))

let range = word.range(of: "ll")!

print(String(format: "Lower Bound: %d", range.lowerBound.encodedOffset))

print(String(format: "Upper Bound: %d", range.upperBound.encodedOffset))



word = word.replacingOccurrences(of: "ll", with: "")

print(String(format: "Word after replacement: %@", word))



for (i, c) in word.enumerated() {

    print(String(format: "Index: %d, Character: %@", i, String(c)))

}

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

add a comment |

Swift is a very powerful language. Try out some of its higher level features.
Try putting this in playground.

var word = "Hello"

print(String(format: "Word: %@", word))

let range = word.range(of: "ll")!

print(String(format: "Lower Bound: %d", range.lowerBound.encodedOffset))

print(String(format: "Upper Bound: %d", range.upperBound.encodedOffset))



word = word.replacingOccurrences(of: "ll", with: "")

print(String(format: "Word after replacement: %@", word))



for (i, c) in word.enumerated() {

    print(String(format: "Index: %d, Character: %@", i, String(c)))

}

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

add a comment |

Swift is a very powerful language. Try out some of its higher level features.
Try putting this in playground.

var word = "Hello"

print(String(format: "Word: %@", word))

let range = word.range(of: "ll")!

print(String(format: "Lower Bound: %d", range.lowerBound.encodedOffset))

print(String(format: "Upper Bound: %d", range.upperBound.encodedOffset))



word = word.replacingOccurrences(of: "ll", with: "")

print(String(format: "Word after replacement: %@", word))



for (i, c) in word.enumerated() {

    print(String(format: "Index: %d, Character: %@", i, String(c)))

}

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

Swift is a very powerful language. Try out some of its higher level features.
Try putting this in playground.

var word = "Hello"

print(String(format: "Word: %@", word))

let range = word.range(of: "ll")!

print(String(format: "Lower Bound: %d", range.lowerBound.encodedOffset))

print(String(format: "Upper Bound: %d", range.upperBound.encodedOffset))



word = word.replacingOccurrences(of: "ll", with: "")

print(String(format: "Word after replacement: %@", word))



for (i, c) in word.enumerated() {

    print(String(format: "Index: %d, Character: %@", i, String(c)))

}

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

answered Nov 23 '18 at 17:55

Sethmr

1,79311332

add a comment |

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