javascript - "Unexpected token, expected ," when I try to do conditional rendering in react with stateless fun

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This is my code:

'use strict'

import React from 'react'
import { connect } from 'react-redux'
import { Panel, Col, Row, Well, Button } from 'react-bootstrap'

const Cart = ({ cart }) => {

  const cartItemsList = cart.map(cartArr => (
    <Panel key={cartArr.id}>
      <Row>
        <Col xs={12} sm={4}>
          <h6>{cartArr.title}</h6>
        </Col>
      </Row>
    </Panel>
  ));

  return (
    { cart[0] &&
      (<Panel header="Cart" bsStyle="primary">
        {cartItemsList}
      </Panel>)
    }
    { !cart[0] &&
      (<div></div>)
    }
    // {
    //   cart[0] ? (<Panel header="cart" bsStyle="primary">{cartItemsList}</Panel>) : (<div></div>);
    // }
  )
}

const mapStateToProps = state => ({
  cart: state.cart.cart
})

export default connect(mapStateToProps)(Cart)

As you can see, I'm trying to render cartItemsList nested inside a bootstrap panel ponent only when cart is not an empty array. However as soon as I use conditional rendering, I get the error "Unexpected token, expected ,". The mented out line of code is the alternative I tried and that gives me the same error. If I get rid of the condition and just render the panel with cartItemsList, it renders without any problems. It's only when I add the condition that I see this error. I was wondering what is causing this error to occur?

This is my code:

'use strict'

import React from 'react'
import { connect } from 'react-redux'
import { Panel, Col, Row, Well, Button } from 'react-bootstrap'

const Cart = ({ cart }) => {

  const cartItemsList = cart.map(cartArr => (
    <Panel key={cartArr.id}>
      <Row>
        <Col xs={12} sm={4}>
          <h6>{cartArr.title}</h6>
        </Col>
      </Row>
    </Panel>
  ));

  return (
    { cart[0] &&
      (<Panel header="Cart" bsStyle="primary">
        {cartItemsList}
      </Panel>)
    }
    { !cart[0] &&
      (<div></div>)
    }
    // {
    //   cart[0] ? (<Panel header="cart" bsStyle="primary">{cartItemsList}</Panel>) : (<div></div>);
    // }
  )
}

const mapStateToProps = state => ({
  cart: state.cart.cart
})

export default connect(mapStateToProps)(Cart)

As you can see, I'm trying to render cartItemsList nested inside a bootstrap panel ponent only when cart is not an empty array. However as soon as I use conditional rendering, I get the error "Unexpected token, expected ,". The mented out line of code is the alternative I tried and that gives me the same error. If I get rid of the condition and just render the panel with cartItemsList, it renders without any problems. It's only when I add the condition that I see this error. I was wondering what is causing this error to occur?

• javascript
• reactjs
• conditional-statements

Share Improve this question Follow asked Jun 30, 2017 at 4:08 avatarhzhavatarhzh 2,40355 gold badges2424 silver badges3636 bronze badges 1

• Could you try wrapping your logic in a <div>? return (<div> ... </div>) – Grandas Commented Jun 30, 2017 at 4:13

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 8

{} is required to put the js expressions inside JSX, here it is not required.

Write it like this without {}:

return (
    cart && cart.length ?
        <Panel header="Cart" bsStyle="primary">
            {cartItemsList}
        </Panel>
    :
        <div>
        </div>
)

Another way of writing same code is:

if(cart && cart.length)
    return(
        <Panel header="Cart" bsStyle="primary">
            {cartItemsList}
        </Panel>
    )
return(
    <div>
    </div>
)

This is my code:

'use strict'

import React from 'react'
import { connect } from 'react-redux'
import { Panel, Col, Row, Well, Button } from 'react-bootstrap'

const Cart = ({ cart }) => {

  const cartItemsList = cart.map(cartArr => (
    <Panel key={cartArr.id}>
      <Row>
        <Col xs={12} sm={4}>
          <h6>{cartArr.title}</h6>
        </Col>
      </Row>
    </Panel>
  ));

  return (
    { cart[0] &&
      (<Panel header="Cart" bsStyle="primary">
        {cartItemsList}
      </Panel>)
    }
    { !cart[0] &&
      (<div></div>)
    }
    // {
    //   cart[0] ? (<Panel header="cart" bsStyle="primary">{cartItemsList}</Panel>) : (<div></div>);
    // }
  )
}

const mapStateToProps = state => ({
  cart: state.cart.cart
})

export default connect(mapStateToProps)(Cart)

As you can see, I'm trying to render cartItemsList nested inside a bootstrap panel ponent only when cart is not an empty array. However as soon as I use conditional rendering, I get the error "Unexpected token, expected ,". The mented out line of code is the alternative I tried and that gives me the same error. If I get rid of the condition and just render the panel with cartItemsList, it renders without any problems. It's only when I add the condition that I see this error. I was wondering what is causing this error to occur?

This is my code:

'use strict'

import React from 'react'
import { connect } from 'react-redux'
import { Panel, Col, Row, Well, Button } from 'react-bootstrap'

const Cart = ({ cart }) => {

  const cartItemsList = cart.map(cartArr => (
    <Panel key={cartArr.id}>
      <Row>
        <Col xs={12} sm={4}>
          <h6>{cartArr.title}</h6>
        </Col>
      </Row>
    </Panel>
  ));

  return (
    { cart[0] &&
      (<Panel header="Cart" bsStyle="primary">
        {cartItemsList}
      </Panel>)
    }
    { !cart[0] &&
      (<div></div>)
    }
    // {
    //   cart[0] ? (<Panel header="cart" bsStyle="primary">{cartItemsList}</Panel>) : (<div></div>);
    // }
  )
}

const mapStateToProps = state => ({
  cart: state.cart.cart
})

export default connect(mapStateToProps)(Cart)

As you can see, I'm trying to render cartItemsList nested inside a bootstrap panel ponent only when cart is not an empty array. However as soon as I use conditional rendering, I get the error "Unexpected token, expected ,". The mented out line of code is the alternative I tried and that gives me the same error. If I get rid of the condition and just render the panel with cartItemsList, it renders without any problems. It's only when I add the condition that I see this error. I was wondering what is causing this error to occur?

• javascript
• reactjs
• conditional-statements

Share Improve this question Follow asked Jun 30, 2017 at 4:08 avatarhzhavatarhzh 2,40355 gold badges2424 silver badges3636 bronze badges 1

• Could you try wrapping your logic in a <div>? return (<div> ... </div>) – Grandas Commented Jun 30, 2017 at 4:13

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 8

{} is required to put the js expressions inside JSX, here it is not required.

Write it like this without {}:

return (
    cart && cart.length ?
        <Panel header="Cart" bsStyle="primary">
            {cartItemsList}
        </Panel>
    :
        <div>
        </div>
)

Another way of writing same code is:

if(cart && cart.length)
    return(
        <Panel header="Cart" bsStyle="primary">
            {cartItemsList}
        </Panel>
    )
return(
    <div>
    </div>
)

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