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[css-values-4] Moved definition of <flex> to CSS Values 4
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‎css-borders-4/Overview.bs‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -336,7 +336,7 @@ The 'border-clip' properties</h3>
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the border edge. The first part is visible, the second is invisible,
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the third part is visible, etc. Parts can be specified with lengths,
338338
percentages, or flexible lengths (expressed by the ''fr'' unit, as per
339-
[[CSS3GRID]]).
339+
[[css-values-4#fractions]]).
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The ''border-clip/normal'' value means
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that the border is not split, but shown normally.
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‎css-grid-1/Overview.bs‎

Lines changed: 16 additions & 58 deletions
Original file line numberDiff line numberDiff line change
@@ -1542,11 +1542,11 @@ Track Sizes</h4>
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15431543
<dt><dfn><<flex [0,∞]>></dfn>
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<dd>
1545-
A non-negative dimension with the unit ''fr'' specifying the track's <dfn dfn noexport>flex factor</dfn>.
1545+
Specifies the track's <dfn dfn noexport>flex factor</dfn>.
15461546
Each <<flex>>-sized track takes a share of the remaining space in proportion to its <a>flex factor</a>.
15471547
For example, given a track listing of ''1fr 2fr'',
15481548
the tracks will take up ⅓ and ⅔ of the <a>leftover space</a>, respectively.
1549-
See [[#fr-unit]] for more details.
1549+
See [[#flexible-tracks]] for more details.
15501550

15511551
Note: If the sum of the <a>flex factors</a> is less than 1,
15521552
they'll take up only a corresponding fraction of the <a>leftover space</a>,
@@ -1850,22 +1850,19 @@ Interpolation/Combination of ''repeat()''</h5>
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They otherwise combine <a lt=discrete>discretely</a>.
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1862-
<h4 id='fr-unit'>
1863-
Flexible Lengths: the ''fr'' unit</h4>
1862+
<h4 id='flexible-tracks'>
1863+
Flexible Tracks</h4>
18641864

1865-
A <dfn export>flexible length</dfn> or <dfn><<flex>></dfn> is a dimension
1866-
with the <dfn value for="<flex>" lt="fr|fr unit">fr</dfn> unit,
1867-
which represents a fraction of the <a>leftover space</a> in the <a>grid container</a>.
1868-
Tracks sized with ''fr'' units are called <dfn>flexible tracks</dfn>
1865+
Tracks sized using <<flex>> values are called <dfn>flexible tracks</dfn>
18691866
as they flex in response to <a>leftover space</a>
18701867
similar to how <a>flex items</a> with a zero base size fill space in a <a>flex container</a>.
18711868

@@ -1876,45 +1873,6 @@ Flexible Lengths: the ''fr'' unit</h4>
18761873
Each column or row's share of the <a>leftover space</a> can be computed as the column or row's
18771874
<code>&lt;flex> * &lt;leftover space> / &lt;sum of all <a>flex factors</a>&gt;</code>.
18781875

1879-
<details class=note>
1880-
<summary><<flex>> values between 0fr and 1fr have a somewhat special behavior:
1881-
when the sum of the flex factors is less than 1,
1882-
they will take up less than 100% of the leftover space.</summary>
1883-
1884-
A track’s <<flex>> value
1885-
is effectively a request for some proportion of the leftover space,
1886-
with ''1fr'' meaning “100% of the leftover space”;
1887-
then if the tracks in that axis are requesting more than 100% in total,
1888-
the requests are rebalanced to keep the same ratio but use up exactly 100% of it.
1889-
However, if the tracks request <em>less</em> than the full amount
1890-
(such as three tracks that are each ''.25fr'')
1891-
then they'll each get exactly what they request
1892-
(25% of the leftover space to each,
1893-
with the final 25% left unfilled).
1894-
See [[#algo-flex-tracks]] for the exact details
1895-
of how leftover space is distributed.
1896-
1897-
This pattern is required for continuous behavior as ''fr'' values approach zero
1898-
(which means the tracks wants <em>none</em> of the leftover space).
1899-
Without this, a ''1fr'' track would take all of the leftover space;
1900-
but so would a ''0.1fr'' track,
1901-
and a ''0.01fr'' track,
1902-
etc.,
1903-
until finally the value is small enough to underflow to zero
1904-
and the track suddenly takes up none of the leftover space.
1905-
With this behavior,
1906-
the track instead gradually takes less of the leftover space
1907-
as its flex factor shrinks below ''1fr'',
1908-
smoothly transitioning to taking none of the leftover space at zero.
1909-
1910-
Unless this “partial fill” behavior is <em>specifically</em> what's desired,
1911-
authors should stick to values &ge; 1;
1912-
for example, using ''1fr'' and ''2fr'' is usually better
1913-
than using ''.33fr'' and ''.67fr'',
1914-
as they're more likely to behave as intended
1915-
if tracks are added or removed.
1916-
</details>
1917-
19181876
When the available space is infinite
19191877
(which happens when the <a>grid container</a>’s width or height is <a>indefinite</a>),
19201878
flex-sized <a>grid tracks</a> are sized to their contents while retaining their respective proportions.
@@ -1925,10 +1883,6 @@ Flexible Lengths: the ''fr'' unit</h4>
19251883
The maximum of those is used as the resolved ''1fr'' length (the <dfn>flex fraction</dfn>),
19261884
which is then multiplied by each <a>grid track</a>’s <a>flex factor</a> to determine its final size.
19271885

1928-
Note: <<flex>> values are not <<length>>s
1929-
(nor are they compatible with <<length>>s, like some <<percentage>> values),
1930-
so they cannot be represented in or combined with other unit types in ''calc()'' expressions.
1931-
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@@ -4902,6 +4856,10 @@ Changes since the <a href="https://www.w3.org/TR/2020/CRD-css-grid-1-20201218/">
49024856
instead use the <a>grid area</a> determined in [[#abspos-items]].</del>
49034857
</blockquote>
49044858

4859+
<li id="change-2020-fr-unit">
4860+
Moved the definition of <<flex>> to [[css-values-4#fractions]],
4861+
as other specs also make use of it.
4862+
(<a href="https://github.com/w3c/csswg-drafts/issues/8027">Issue 8027</a>)
49054863
</ul>
49064864

49074865
<h3 id="changes-202008">

‎css-grid-2/Overview.bs‎

Lines changed: 15 additions & 56 deletions
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@@ -1940,22 +1940,19 @@ Interpolation/Combination of ''repeat()''</h5>
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They otherwise combine <a lt=discrete>discretely</a>.
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1952-
<h4 id='fr-unit'>
1953-
Flexible Lengths: the ''fr'' unit</h4>
1952+
<h4 id='flexible-tracks'>
1953+
Flexible Tracks</h4>
19541954

1955-
A <dfn export>flexible length</dfn> or <dfn><<flex>></dfn> is a dimension
1956-
with the <dfn value for="<flex>" lt="fr|fr unit">fr</dfn> unit,
1957-
which represents a fraction of the <a>leftover space</a> in the <a>grid container</a>.
1958-
Tracks sized with ''fr'' units are called <dfn>flexible tracks</dfn>
1955+
Tracks sized using <<flex>> values are called <dfn>flexible tracks</dfn>
19591956
as they flex in response to <a>leftover space</a>
19601957
similar to how <a>flex items</a> with a zero base size fill space in a <a>flex container</a>.
19611958

@@ -1966,45 +1963,6 @@ Flexible Lengths: the ''fr'' unit</h4>
19661963
Each column or row's share of the <a>leftover space</a> can be computed as the column or row's
19671964
<code>&lt;flex> * &lt;leftover space> / &lt;sum of all <a>flex factors</a>&gt;</code>.
19681965

1969-
<details class=note>
1970-
<summary><<flex>> values between 0fr and 1fr have a somewhat special behavior:
1971-
when the sum of the flex factors is less than 1,
1972-
they will take up less than 100% of the leftover space.</summary>
1973-
1974-
A track’s <<flex>> value
1975-
is effectively a request for some proportion of the leftover space,
1976-
with ''1fr'' meaning “100% of the leftover space”;
1977-
then if the tracks in that axis are requesting more than 100% in total,
1978-
the requests are rebalanced to keep the same ratio but use up exactly 100% of it.
1979-
However, if the tracks request <em>less</em> than the full amount
1980-
(such as three tracks that are each ''.25fr'')
1981-
then they'll each get exactly what they request
1982-
(25% of the leftover space to each,
1983-
with the final 25% left unfilled).
1984-
See [[#algo-flex-tracks]] for the exact details
1985-
of how leftover space is distributed.
1986-
1987-
This pattern is required for continuous behavior as ''fr'' values approach zero
1988-
(which means the tracks wants <em>none</em> of the leftover space).
1989-
Without this, a ''1fr'' track would take all of the leftover space;
1990-
but so would a ''0.1fr'' track,
1991-
and a ''0.01fr'' track,
1992-
etc.,
1993-
until finally the value is small enough to underflow to zero
1994-
and the track suddenly takes up none of the leftover space.
1995-
With this behavior,
1996-
the track instead gradually takes less of the leftover space
1997-
as its flex factor shrinks below ''1fr'',
1998-
smoothly transitioning to taking none of the leftover space at zero.
1999-
2000-
Unless this “partial fill” behavior is <em>specifically</em> what's desired,
2001-
authors should stick to values &ge; 1;
2002-
for example, using ''1fr'' and ''2fr'' is usually better
2003-
than using ''.33fr'' and ''.67fr'',
2004-
as they're more likely to behave as intended
2005-
if tracks are added or removed.
2006-
</details>
2007-
20081966
When the available space is infinite
20091967
(which happens when the <a>grid container</a>’s width or height is <a>indefinite</a>),
20101968
flex-sized <a>grid tracks</a> are sized to their contents while retaining their respective proportions.
@@ -2015,10 +1973,6 @@ Flexible Lengths: the ''fr'' unit</h4>
20151973
The maximum of those is used as the resolved ''1fr'' length (the <dfn>flex fraction</dfn>),
20161974
which is then multiplied by each <a>grid track</a>’s <a>flex factor</a> to determine its final size.
20171975

2018-
Note: <<flex>> values are not <<length>>s
2019-
(nor are they compatible with <<length>>s, like some <<percentage>> values),
2020-
so they cannot be represented in or combined with other unit types in ''calc()'' expressions.
2021-
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<!--
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@@ -5503,6 +5457,11 @@ Changes since the <a href="https://www.w3.org/TR/2020/CRD-css-grid-2-20201218/">
55035457
<del>However, if the <a>grid container</a> parent is also the generator of the absolutely positioned element's <a>containing block</a>,
55045458
instead use the <a>grid area</a> determined in [[#abspos-items]].</del>
55055459
</blockquote>
5460+
5461+
<li id="change-2020-fr-unit">
5462+
Moved the definition of <<flex>> to [[css-values-4#fractions]],
5463+
as other specs also make use of it.
5464+
(<a href="https://github.com/w3c/csswg-drafts/issues/8027">Issue 8027</a>)
55065465
</ul>
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55085467
<h3 id="changes-202008">

‎css-values-4/Overview.bs‎

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@@ -2918,6 +2918,75 @@ Combination of <<position>></h4>
29182918
as a <<length-percentage>>.
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-->
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<h3 id="fractions">
2932+
Flexible lengths: the <<flex>> type</h3>
2933+
2934+
Fraction values are non-negative <<dimension>>s denoted by
2935+
<dfn id="flex-value">&lt;flex></dfn>.
2936+
The unit identifier is <dfn value for="<flex>" lt="fr|fr unit">fr</dfn>.
2937+
2938+
These values specify
2939+
<dfn export lt="flexible length">flexible lengths</dfn>.
2940+
Each length defines a portion of a given space
2941+
which is specified by the context the type is used in.
2942+
2943+
Note: <<flex>> values are not <<length>>s
2944+
(nor are they compatible with <<length>>s, like some <<percentage>> values),
2945+
so they cannot be represented in or
2946+
combined with other unit typesin ''calc()'' expressions.
2947+
2948+
<details class=note>
2949+
<summary><<flex>> values between 0fr and 1fr have a somewhat special behavior:
2950+
when the sum of the flex factors is less than 1,
2951+
they will take up less than 100% of the leftover space.</summary>
2952+
2953+
A <<flex>> value is effectively a request for some proportion of the leftover space,
2954+
with ''1fr'' meaning “100% of the leftover space”;
2955+
then, if the used space sums up to more than 100% of the available space,
2956+
the requested space is rebalanced to keep the same ratio
2957+
but use up exactly 100% of it.
2958+
However, if the sum is <em>less</em> than the full amount
2959+
(such as three times ''.25fr'')
2960+
then the requested space is exactly what's used
2961+
(25% of the leftover space for each fraction,
2962+
with the final 25% left unfilled).
2963+
2964+
This pattern is required for continuous behavior as ''fr'' values approach zero
2965+
(which means the leftover space is <em>not</em> occupied by any fractions).
2966+
Without this, a ''1fr'' value would take all of the leftover space;
2967+
but so would a ''0.1fr'' value,
2968+
and a ''0.01fr'' value,
2969+
etc.,
2970+
until finally the value is small enough to underflow to zero
2971+
and the fractions suddenly take up none of the leftover space.
2972+
With this behavior,
2973+
the fractions instead gradually take less of the leftover space
2974+
as their flex factor shrinks below ''1fr'',
2975+
smoothly transitioning to taking none of the leftover space at zero.
2976+
2977+
Unless this “partial fill” behavior is <em>specifically</em> what's desired,
2978+
authors should stick to values &ge; 1;
2979+
for example, using ''1fr'' and ''2fr'' is usually better
2980+
than using ''.33fr'' and ''.67fr'',
2981+
as they're more likely to behave as intended
2982+
if fractions are added or removed.
2983+
</details>
2984+
2985+
Note: <<flex>> values are not <<length>>s
2986+
(nor are they compatible with <<length>>s, like some <<percentage>> values),
2987+
so they cannot be represented in or combined with other unit types in ''calc()'' expressions.
2988+
2989+
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<!--
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████████ ██ ██ ██ ██ ██████ ██████
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@@ -5244,6 +5313,8 @@ Recent Changes</h3>
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<li>Added formal definitions for <<url()>> and <<src()>> (in addition to <<url>>).
52455314
<li>Rephrased fragment-only URLs in terms of tree-scoped references.
52465315
(<a href="https://github.com/w3c/csswg-drafts/issues/3320">Issue 3320</a>)
5316+
<li>Moved the definition of <<flex>> from [[css-grid-1]] to this specification.
5317+
(<a href="https://github.com/w3c/csswg-drafts/issues/8027">Issue 8027</a>)
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</ul>
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52495320
Substantial changes since <a href="https://www.w3.org/TR/2021/WD-css-values-4-20211216/">16 December 2021 WD</a>:

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