forked from mirrors/jj
1c0bde1a2b
A lambda expression will be allowed only in .map() operation. The syntax is
borrowed from Rust closure.
In Mercurial, a map operation is implemented by context substitution. For
example, 'parents % "{node}"' prints parents[i].node for each. There are two
major problems: 1. the top-level context cannot be referred from the inner map
expression. 2. context of different types inserts arbitrarily-named keywords
(e.g. a dict type inserts "{key}" and "{value}", but how we could know.)
These issues should be avoided by using explicitly named parameters.
parents.map(|parent| parent.commit_id ++ " " ++ commit_id)
^^^^^^^^^ global keyword
A downside is that we can't reuse template fragment in map expression. Suppose
we have -T commit_summary, -T 'parents.map(commit_summary)' doesn't work.
# only usable as a top-level template
'commit_summary' = 'commit_id.short() ++ " " ++ description.first_line()'
Another problem is that a lambda expression might be confused with an alias
function.
# .map(f) doesn't work, but .map(g) does
'f(x)' = 'x'
'g' = '|x| x'
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|---|---|---|
| .. | ||
| common | ||
| test_abandon_command.rs | ||
| test_alias.rs | ||
| test_branch_command.rs | ||
| test_cat_command.rs | ||
| test_checkout.rs | ||
| test_commit_command.rs | ||
| test_commit_template.rs | ||
| test_concurrent_operations.rs | ||
| test_config_command.rs | ||
| test_debug_command.rs | ||
| test_describe_command.rs | ||
| test_diff_command.rs | ||
| test_diffedit_command.rs | ||
| test_duplicate_command.rs | ||
| test_edit_command.rs | ||
| test_git_clone.rs | ||
| test_git_colocated.rs | ||
| test_git_fetch.rs | ||
| test_git_import_export.rs | ||
| test_git_push.rs | ||
| test_git_remotes.rs | ||
| test_gitignores.rs | ||
| test_global_opts.rs | ||
| test_init_command.rs | ||
| test_interdiff_command.rs | ||
| test_log_command.rs | ||
| test_move_command.rs | ||
| test_new_command.rs | ||
| test_obslog_command.rs | ||
| test_operations.rs | ||
| test_rebase_command.rs | ||
| test_resolve_command.rs | ||
| test_restore_command.rs | ||
| test_revset_output.rs | ||
| test_show_command.rs | ||
| test_sparse_command.rs | ||
| test_split_command.rs | ||
| test_squash_command.rs | ||
| test_status_command.rs | ||
| test_support_command.rs | ||
| test_templater.rs | ||
| test_undo.rs | ||
| test_unsquash_command.rs | ||
| test_untrack_command.rs | ||
| test_workspaces.rs | ||