Javascript, what does the 1 in slice(1) refer to in this program? - Stack Overflow

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In this program, I understand (I think) that paragraph.charAT(0) = "%" checks whether the first character in paragraph is equal to %, i.e. the counting starts at 0, so charAT(0) is the first character

However, in the line, paragraph.slice(1), what does the 1 refer to? Is it slicing off the first character?, which in this case will be at 0 position?

function processParagraph(paragraph) {
  var header = 0;
  while (paragraph.charAt(0) == "%") {
    paragraph = paragraph.slice(1);
    header++;
  }

  return {type: (header == 0 ? "p" : "h" + header),
          content: paragraph};
}

show(processParagraph(paragraphs[0]));

In this program, I understand (I think) that paragraph.charAT(0) = "%" checks whether the first character in paragraph is equal to %, i.e. the counting starts at 0, so charAT(0) is the first character

However, in the line, paragraph.slice(1), what does the 1 refer to? Is it slicing off the first character?, which in this case will be at 0 position?

function processParagraph(paragraph) {
  var header = 0;
  while (paragraph.charAt(0) == "%") {
    paragraph = paragraph.slice(1);
    header++;
  }

  return {type: (header == 0 ? "p" : "h" + header),
          content: paragraph};
}

show(processParagraph(paragraphs[0]));

• javascript

Share Improve this question Follow asked Feb 25, 2011 at 3:02 mjmitchemjmitche 2,06766 gold badges2525 silver badges3131 bronze badges 2

• 1 see here. MDC is a great resource for javascript. – aaronasterling Commented Feb 25, 2011 at 3:07
• See also What is the difference between String.slice and String.substring in JavaScript? – Rudu Commented Feb 25, 2011 at 3:14

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4 Answers 4

Sorted by: Reset to default 9

It extracts a substring starting at index 1 (2nd character) of the paragraph string.

For example, consider this:

var paragraph = "Hi my name is Russell";
console.log( paragraph.slice(1) ); //returns 'i my name is Russell'

.slice

string.slice(beginslice[, endSlice])

Extracts a section of a string and returns a new string.

It returns everything after the first character, essentially cutting the first character off.

It removes the first character from the string and returns that without altering the original string. I remend you look at the documentation for slice.

it's slicing off the first character (which is a "%")

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